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Kevin Muramatsu

How-To: Installing A Free-Floated Handguard On Your AR-15

Upgrading from a standard to a free-floated handguard can increase your AR-15’s accuracy potential, and it isn’t difficult following this procedure.

How to swap out for a free-floated handguard:

  • Remove upper receiver and pull back delta rings to remove standard handguard.
  • Remove retaining pins from the A-Frame — after the gas tube is removed.
  • Use a special bench block to keep rest of upper elevated.
  • Once pins are removed, gas block collar should slide off the barrel.
  • Upon removing barrel retainer nut, new free-floated handguard is ready.
  • Before new handguard is fitted, a new minimized gas block must be installed.
  • Once the gas system is in place, tighten handguard onto nut.

This is the typical process to change a standard handguard to a free-floated handguard. Start with no lower assembly. The upper assembly should be detached and in a bench vise. You will want to use your upper receiver blocks for this entire sequence.

The first thing is to pull back on the delta ring to remove the lower piece. It just seems easier usually to do the bottom first. The piece should be lowered from the back and then pulled out of the cup at the front. Follow this up by then removing the top piece. You should now see an upper assembly with no handguard, with the barrel and gas tube naked and exposed to all creation. This is way easy with a forend/handguard tool. I will restate that I prefer to remove the gas tube at this time as well, so as not to risk banging it up when we start banging on the front sight block.

You will have to remove the front sight’s tapered retaining pins from the bottom of the A-frame. They are TAPERED, which means they only go out one way, and some companies think it’s just the coolest thing ever to really, really jam those things in there. Granted, you don’t ever want them coming out without actually wanting them to come out, but they are often in there so tight that you might have to cut or drill them out. We’re talking baby bunny under a porch step here.

Sometimes you can get them out by putting the barrel or the sight tower in the vise, and most times you can get them out using a specialty bench block. I wish I could tell you a universal way to get them out easily, but I can’t. Some are relatively easy, and some aren’t.

The specialty bench block to which I refer is the front sight bench block that Brownells sells. It is machined out so that the front sight tower will fit either way into it and you can hammer out the pins; it even has directions on it.

You will want to support the rest of the upper on a similarly elevated surface for ease of use. By the way, they virtually always go out from left to right. There is a noticeable difference in diameter, left to right. Use a short, thick punch to get them started and then a longer punch to finish pushing them out to the right. The front sight tower may be quite tightly attached still, so a little twisting and possibly a little propane heat on the tower rings may be in order.

Once it is off the gas block collar of the barrel, it should easily slide off the muzzle, assuming you have removed whatever muzzle device might be present. It can however be on tightly and require a little heat to expand the rings. Take care to not kink the gas tube if you left it in place. If you twist the assembly too far with the gas tube installed, you will likely damage the tube. It’s supposed to have a bend in it but not more than it started with. Honestly, it’s best to remove the tube before you play with the block, but not necessarily mandatory.

Now the barrel should be clear of stuff. If by chance there is something still on the barrel, now would be the time to remove it. Since we are assuming a standard rifle upper here, there should not be anything else there.

Here is where you take your handy dandy action wrench to remove the barrel retainer nut. Once that is done, you are ready to install your new handguard. Let’s for the sake of argument say that it is a JP Enterprises Modular handguard. This is one of the less common styles of handguard, using both inner and outer retainer nuts.

The outer nut is screwed onto the receiver, often with thread locking compound to hold it in place in alignment while the inner nut is tightened against the barrel extension. The same amount of torque is used to secure the nut as a normal nut, around 30–100 ft/lbs of torque, and if you don’t know what that feels like, then you should borrow a torque wrench from your buddy in the auto shop.

In the case of this JP handguard, the body of the unit is a simple extruded tube with slots cut in it for ventilation. The rear end of the tube is counter-bored to accept the outer handguard nut and has six holes around it to fasten it to the nut. However, since we are replacing a carbine-length standard handguard with a rifle-length free-floating handguard, we now have to install a minimized gas block first, since it is going to be fully inside the confines of the tube and virtually impossible to install correctly with the tube emplaced. If you are going to install accessory rails to this tube, this too should be done before the tube is attached.

This JP tube uses six flat head screws to hold the tube to the nut. The tube can inadvertently be installed upside down, so don’t do that. With these six screws attached, you are pretty much ready to go, as long as you remembered to install the gas tube and gas block.

Of course, you no longer have a front sight. Perhaps you decided that you don’t really want one and you are going to use only optics. OK, so you’re one of those…people. Well, I guess that’s OK, and you can stop here, since your super optic mega scope will take care of everything. If you aren’t one of those…people, then you can still mount a front sight to the front end of the handguard tube. JP sells partial or full sized rails for that purpose. Flip up sights can still be used effectively with optics, and particularly offset sights are a good choice for rifles with high magnification scopes used as the primary sighting device. 

Editor's Note: This article is an excerpt from Gun Digest Guide to Customizing Your AR-15.

How To: Choosing A Flash Suppressor, Muzzle Brake And Compensator

The right muzzle device — whether it's a flash hider, compensator or muzzle brake — is an often-overlooked feature when shopping for an AR. But it shouldn't be, as each enhances the rifle in its own way. Understanding and selecting the right option for your black gun can go a long way in making a more effective firearm.

muzzle device - custom AR
Discover how to build the gun of your dreams with Gun Digest Guide to Customizing Your AR-15.

Flash Suppressor

A flash suppressor or flash hider reduce the muzzle flash caused by still-burning powder exiting the barrel behind the bullet. Some powders have flash retardants in them, so a smaller signature will be seen. Others are naturally bright, and using ammo with these powders will create quite the bloom when fired. Furthermore, rifles with muzzle brakes attached tend to flash brightly, but in a more directional manner.

Here’s an example. I once conducted an experiment to see how effective a couple of these were. Now this wasn’t a truly scientific experiment, but it still was pretty definitive. I shot my 16-inch carbine nekkid muzzle, with a standard A2 flash suppressor, and with a Yankee Hill Machine Phantom 5C2 flash suppressor. I did this around 8 p.m. in the autumn, dark enough that there was little ambient light. The ammo used was Winchester 5.56 (Q3131A for a part number if you care), made in Israel for Olin Industries (owns Winchester name for ammo), known for producing a bright flash.

Muzzle Device - AR flash hider
The Smith Enterprises Vortex flash suppressor is arguably the most effective model on the market and has been copied repeatedly. The long tines vibrate as the bullet passes through, breaking up the burning powder. You will be lucky to see a spark come out of this one.

The first shot with the nekkid muzzle produced an orange basketball-sized globular flash. It was bright and did in fact disrupt the night vision I had at the time. I followed this up with the Mil-Spec A2 flash suppressor on the muzzle.

The result when fired was a small orange flash about the size of the average Clementine orange. Then I fired with the Phantom and I was duly impressed. There was no flash visible to me or the observers (my extended family), but there was a single spark that traveled a few feet from the muzzle before extinguishing. A. Spark.

Anyone within several hundred meters would have seen the nekkid muzzle flash, and within at least a hundred meters would have seen the A2 flash. I doubt anyone within as little as 20 feet would have seen the spark and they would have had to have been looking directly at me to even catch a glimpse of it.

The Phantom, at least that model, is a superb flash suppressor and it is even pretty affordable. You can get one for under thirty bucks, and there are several models that have closed bottoms so you don’t kick up dust when firing prone. They work just as well as the standard models. They are similar to the A2 flash suppressor, which also has five open ports on the top and sides, but has a closed bottom. They have the added minor benefit that they combat muzzle rise slightly like dedicated muzzle compensators.

Back when I tried this, the only options were the Mil-Spec A1 (six evenly spaced ports), A2, the Phantom and the Vortex (Smith Industries) and the copies thereof. Now, you’ll get a headache trying to figure something out and you will ultimately probably decide based purely on the aesthetics of the device.


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There are a number of well-functioning flash suppressor on the market now, though the best seem to be variants of the Phantom or the Vortex. The Vortex has long tines similar to the Phantom, but the tines are not connected at the end. This allows the tines to vibrate like a tuning fork when the gun is fired, and this is the mechanism to disperse the flash. These types of flash hiders are arguably the most effective designs, but also tend to approach $50 in cost. You also have to watch where your muzzle goes (you already do anyway, right) or you might get stuff stuck in between the tines.

Compensators

Muzzle device - AR
The Vais compensator can sometimes be found on ARs but it is usually seen on traditional hunting rifles. The large series of holes vent gas 90 degrees to the bore axis, all the way around. This particular brake requires non-standard threads. Be aware of things such as thread pitches when you order your muzzle devices from retailers.

The term compensator is almost always ascribed to a muzzle device that is designed to reduce muzzle rise, not necessarily recoil. Indeed, if the device pushes the muzzle down, more recoil force is often transmitted straight back, enhancing felt recoil while keeping the muzzle movement minimal. It is true, however, that compensators and muzzle brakes can be combined effectively in the same unit, and we’ll talk about those in the following section on muzzle brakes.

The vast majority of compensators are designed with a common element of holes or slots on the top. These slots may extend somewhat to the side but then they become more like brakes. When the bullet exits the barrel and passes through the compensator, the expanding gas behind the bullet exits through these holes before exiting the “muzzle” of the comp. This produces a jet of gas that is going straight up or up and to the rear, acting as a counterforce to the rise of the muzzle. The higher the pressure of the gas behind the bullet the more effective the comp.

The A2 flash suppressor also acts as a compensator, where the older A1 flash suppressor did not. Many companies, in particular YHM, make compensator or brake versions of their flash suppressors that look virtually identical.

Muzzle Brake

muzzle device ARs
One of the originals. The JP Recoil Eliminator is huge and works extremely well. However, it often looks out of place on barrels because of its large profile. The tactical models on the right are more common.

Brakes are designed a bit differently and are typified by the inclusion of baffles in the design. They work by using the expanding gas, as the compensator does, but in a different manner. These are designed to reduce felt recoil, not necessarily muzzle rise.

To do this, they have what amounts to virtual expansion chambers formed by the baffles. When the expanding gas following the bullet hits the rear face of the baffles, the gas literally pushes the baffles, the brake and the rifle it is attached to, forward. The gas then vents out the large holes on the side of the brake.

Most brakes also incorporate a few holes on the top to vent some of the gas up, giving them very good muzzle compensation in addition to the braking. You will see these in variations of two basic designs. The first is simply a hollow cylinder, bored out with dozens of holes all the way around the outside of the comp. These are reasonably effective as long as there is a front face to deflect some of the gas out, and are typified by the Williams muzzle brakes.

The second type is much larger and will have the large flat baffles and large side vent ports and most of these work incredibly well. The JP Enterprises, Dreadnought Industries and other similar models are very popular in the varminting and sporting realms because of the ease of follow-up shooting.

A very important note must be made. Compensators and muzzle brakes are so loud that you must have hearing protection. Do not shoot these guns indoors if you can help it. The concussion on these can be quite powerful and much of it is directed to the side or rear. Do not teach new shooters, especially women (who seem to be particularly sensitive to concussive effects) to shoot with centerfire rifles equipped with these muzzle devices.

On the other hand, if you are at the range and you have a couple stupid couch commando tough guys next to you (you know the type, too tough to wear sissy hearing protection, and smells like he hasn’t showered in an week), you can get rid of him quickly by getting out your compensated rifle and ripping off five or six shots one right after the other. He will quickly want to be elsewhere.

This article is an excerpt from Gun Digest Guide to Customizing Your AR-15.

AR-15 Optics: Red Dots

The C-More Scout mount is a great way to place a red dot on your carry handle equipped rifle, though in this case it’s sitting on a detachable carry handle. You can still use the iron sights, and for the most part, users of this style of mount will “co-witness” the dot to the irons.
The C-More Scout mount is a great way to place a red dot on your carry handle equipped rifle, though in this case it’s sitting on a detachable carry handle. You can still use the iron sights, and for the most part, users of this style of mount will “co-witness” the dot to the irons.

Now is a great time to add AR-15 optics to your rifle or carbine. In Part I, Muramatsu looks at the latest in red dot scopes for ARs.

he Bushnell TRS-25 mounted on the author’s scratchbuild, a 5.56 from everywhere. This model’s color closely matches the Burned Bronze Cerakote on the rifle and they make a good pair for close range de-Commiefying work.
he Bushnell TRS-25 mounted on the author’s scratchbuild, a 5.56 from everywhere. This model’s color closely matches the Burned Bronze Cerakote on the rifle and they make a good pair for close range de-Commiefying work.

The original idea behind the red dot scope was to have a single illuminated aiming point, sort of like a crosshairs in a riflescope, but at zero magnification, with a wide field of view. There are a lot of different sized dots, different colored dots (don’t have to be red, but most are, and the originals were), not dots at all but circles, triangles, whatever, powered and unpowered, small and large.

The basic theoretical red dot sight is encapsulated in a smallish housing roughly 30-50 mm in diameter and three or four inches long. And black. Black is still the new black. A diode inside the back of the housing shines a beam forward that reflects off the front lens assembly back through the rear lens into the shooter’s ocular sensory apparatus.

Adjustments are present to move that dot around the inside of the optic so that you can adjust the point of impact. There is generally no magnification. The dot covers a certain-sized circle at 100 yards. 4 MOA dots are common that cover a four-inch circle at that range. In a way, the dot size can allow some basic rough ranging ability, but the dot size can be variable and often is of different sizes for different tasks.

Larger dots are better at short ranges where precision is secondary to speed, and smaller dots, as small as 1 MOA or less, are used past 100 yards with good precision. Intensity settings on the theoretical red dot scope are user adjustable so that you can set it high for bright sunlight or quite low for those times when you are protecting your home in the dead of night.

This theoretical model will also have a clamp mounting system integral to the housing so that it can be slapped down on a Picatinny or Weaver mounting rail. The theoretical model, since it is basic, is also cheap and can be found for under $50. There are all kinds of models available.

 The “standard” Aimpoint Red dot optic looks like this CompM3. This is the civilian counterpart to the M68 CCO.
The “standard” Aimpoint Red dot optic looks like this CompM3. This is the civilian counterpart to the M68 CCO.

Let’s expand out from there. You can go up to the $100 range and find something with a little more in the way of flexibility. A Bushnell TRS-25 red dot scope is a nicely made, compact optic with familiar looks. There is a downside: it is going to need a Picatinny rail riser. UTG makes a super and super priced riser, that looks like it was meant to be used with the TRS-25, for about ten bucks.

Remember, an AR optic needs to be high up in order to raise it to the correct usable height. Up to this point, the battery life of these red dots mentioned is in the dozens of hours, using a watch battery as a power source, usually a CR2032 button. This battery is common (get it at any department store) and inexpensive.

The next tier of red dots gets expensive. This is because we are entering into the tactical realm of this particular universe. The previously mentioned types are generally hunting use or relatively low impact resistant, but are still commonly used as entry points on ARs and related rifles. Tactical, competition, and military/LEO shooters have a much more demanding agenda with red dots, just like with riflescopes.

Likely the most well-known red dot optic at this level is the Aimpoint. This is the small scope seen on many rifles carried by our military and is known there as the M68 Close Combat Optic. This model is based on the Aimpoint CompM2 red dot scope. In use it is much like the theoretical baseline model but with some under-the-surface enhancements. Battery life has been extended to the tens of thousands of hours.

This Meprolight reflex sight uses no power source except what can be taken from the wild outdoors. Sort of. It works during the day with fiberoptics, with light from the sun. At night, it illuminates using Tritium, derived from seawater.
This Meprolight reflex sight uses no power source except what can be taken from the wild outdoors. Sort of. It works during the day with fiberoptics, with light from the sun. At night, it illuminates using Tritium, derived from seawater.

You can leave these things on at full power for well over a year. The housings are reinforced and overall, the durability of the Aimpoint red dots is an order of magnitude above the previous tier of red dot optics. The CompM2 is pretty much obsolete now and they are a couple generations past it. But it is still in production and still well sold nationwide.

A different but still common alternative to the Aimpoint has been the EoTech Holosight. First of all it’s not round. It’s more squarish and boxy. If you are into squarish and boxy then boy, is the Holosight for you. Rather than using a red diode, the Holosight uses a “laser.” I point that out simply to be a know-it-all.

It doesn’t really matter in the grand scheme of things. The effect is the same in that you have a dot, or in this case a circle dot that appears to project onto the target but never leaves the confines of the optic body. Rather than using dials to adjust intensity, it has buttons either on the rear or the side of the housing that activate and adjust up and down accordingly.

The fun part about this model is that is uses the common AA battery, or the becoming common CR123 battery. Formerly used solely in cameras, the CR123 is regularly used in optics and tactical lights so that it is much more common. This is unlike the 1/3N battery that earlier Aimpoints used and you had to dig up online or at Radio Shack.

Eotech Holosights are also very popular. This is a basic 512 model that sells for around $400 and uses AA batteries, for those of you not yet into the Lithium age.
Eotech Holosights are also very popular. This is a basic 512 model that sells for around $400 and uses AA batteries, for those of you not yet into the Lithium age.

There are a host of Holosight models (same with Aimpoint) that you can choose from, based on requirements and cost. This tier of red dots ranges from $300 to over $600. Fortunately most now come with integral Picatinny mounts from the factory, so you don’t have to pay extra for mounting hardware. They even come in something other than black, with several models available in a desert tan color. There are different reticles available too, the craziest one being on the Brownells model that looks like a biohazard symbol.

Micro-red dots are also increasingly common, and as the name would suggest, are quite small. These include the JP JPoint, Burris FastFire, Docter Optics red dot, Trijicon RMR, and others. They are small, very lightweight, use button batteries and last a long time, and often are constantly on, with no on/off switch, using a light sensor to self-regulate brightness. Prices come within a wide range. These optics are generally used not as primary sighting devices but as secondaries, mounted offset on the receiver or handguard, or to the primary scope’s mounting system and used only when use of the primary would not be optimal.

 This micro-red dot from Sightmark represents a good quality, low price model of micro. It also has a fun little sun shade overhang, and it’s green rather than red.
This micro-red dot from Sightmark represents a good quality, low price model of micro. It also has a fun little sun shade overhang, and it’s green rather than red.

The final (at least for now) tier of red dots is rarely red and there are only a few models to choose from. Most of these are passively powered, either by the great firebox in the sky or by radioactivity and usually by both. Models like the Trijicon Tri-power and the Meprolight optics use Tritium to make a visible reticle in subdued light and fiberoptic technology to illuminate the rest of the time, and they do so in a way that self regulates to ambient conditions.

In a way, what goes in comes out again in a perfectly visible, perfectly intense reticle. Meprolight calls it an Electro-optical sight, but the idea is that you don’t have to do anything to the sight. You don’t have to turn it on. You don’t have to play with settings. Nothing. But this convenience comes at a higher price tag.

It’s pretty clear that red dot sights are in a very real manner similar to the traditional magnifying optics in one crucial aspect: price. You get what you pay for. If you only want to spend $100 you will get a unit that is somewhat bulky or has relatively short battery life, works well, but is made in the PRC. If you want to spend $300 or more, you will get a more streamlined or lightweight unit that has battery life measured in the hundreds or thousands of hours, works really well, and is made in the USA, Japan, Israel, Germany, or Sweden, with a lifetime warrantee.

This article is an excerpt from Gun Digest Guide to Customizing Your AR-15.

Lighting Up Your Handgun with Tritium Sights

Tritium sights give shooters the advantage of maintaining their sight picture in low light situations. Photo: <a href="https://www.trijicon.com" target="_blank">Trijicon</a>
Tritium sights give shooters the advantage of maintaining their sight picture in low light situations. Photo: Trijicon

The trouble with most factory handgun sights is when it gets dark, you can’t see them, unless you possess infrared-detecting eyes. For those heat blinded members of society, like myself, then shoot for the tritium sights.

Of particular interest to those who purchase HD or SD guns is the existence of these “glow–in-the-dark” sights. While there are phosphorescent painted sights available (you shine a light on it for a few seconds and it glows), this is not the style of which I speak.

No, I mean the radioactivity glow-in-the-dark kind. I mean putting nuclear physics to work for little ole you. If the light is so subdued that you can’t see your sights, then you really can’t shoot effectively. Sights that are powered by Tritium are the solution. In the dark, these sights produce a low-power eerie glow that is easily seen in the dark and will not destroy your night vision.

It is difficult to overestimate the availability of tritium sights. There are tritium sights made for just about every handgun ever made. The commonality of 1911 pistols has generated a market all of its own, with no less than ten manufacturers offering tritium sights for that pistol.

For the most part you are looking at simple dots that illuminate in the dark and they are surrounded by a white ring for day usage. Actually the dots are constantly illuminated, but that illumination is washed out by daylight or by the intensity of the artificial lighting that most non-cavemen have come to appreciate, to the point that the enhancement can’t be seen except in very low light conditions. You don’t want them to be too bright or your own night vision will be ruined as well.

Sight movers, like this Glock model from MGW, are the best way to shift sights around or remove them
Sight movers, like this Glock model from MGW, are the best way to shift sights around or remove them

Instillation
You might find a sight slot that is loose fitting and the sight is held in by a set screw tensioned against the bottom of the slot. These sights are easy-peasy movable, but if that set screw walks your sight will just fall off. The large majority of sights are press fit into the sight slot and you will then have two not-so-great options for moving them, or for that matter installing them at all.

Let’s say that you want to do it yourself. The first option is to take a hammer and a punch (brass or plastic, NOT steel) and tap the sight out of its slot. Then you tap the new sight back in, preferably with the correct side with the dots facing the rear. Ahhh, crrraaaap!!! You went too far! Now you have to beat it back the other way, at which point you will go too far again. You do this a couple more times then take it to the range, shoot it, it’s still two inches to the right at ten yards, and you go back home and adjust it again. Pain in the old caboose, that is.

The second option is to purchase a sight pusher tool. There are some high-quality examples but the hitch is that they are easily as expensive as your new tritium sights, and with few exceptions, they are made unique to each gun. The Glock sight tool that I have works very well. But it is only made to use Glock factory sights and their unique shape, and Glock slides.

You can insert other sights but not as smoothly, since the contours on the sight engagement interface don’t match anyone else’s sights. Theoretically, other slides could be stuck on the tool, but again, not perfectly, and perfectly is the whole point to having a gun-specific sight pusher. These tools mitigate or eliminate damage caused by the switching process by exactly fitting the parts to be joined or separated.

The front sight on most pistols is inserted in a dovetail slot and should be drifted out gently to one side, according to the directions in the new sight package. Others need to be staked, like some 1911 front sights. Glock front sights are retained by a screw in the bottom of the slide roof that goes up into the sight body. Most replacement Glock front sights will come with a tool for installing this. You can also get one in the Wheeler Engineering screwdriver kit or from Brownells.

Editor's Note: This article is an excerpt from the book Maintaining & Accessorizing Firearms.

Photo Gallery: 20 Semi-Auto Handguns of Gun Digest 2015

From concealed carry handguns, to dedicated target blasters, to exquisite show pieces for the gun collector, there is something for every handgunner in this semi-auto handgun gallery from Gun Digest 2015.

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Modular AR Trigger: Simple AR Accuracy Upgrade

Aftermarket AR triggers like those from Timney are relatively easy to install. The complete process can be finished in about 15 minutes.
Aftermarket AR triggers like those from Timney are relatively easy to install. The complete process can be finished in about 15 minutes.

Probably the easiest means of bettering your trigger pull is to install a modular AR trigger assembly. These have become all the rage. Kevin Muramatsu goes over the finer points of installing this quick and easy AR-15 upgrade.

There are a number of examples available and every one of them is a genuine improvement on the factory fire control. They will either be single or two stage, though mostly single stage. They install pretty much the same all over. The point is pretty much a function of your own ease.

Emplacing a modular unit is child’s play compared to installing one of the non-modular units and is quick and simple, if somewhat more expensive at times. You pull the existing safety to the side in the same procedure you followed earlier for the non-modular units. While in some cases in the non-modular units you can get by without doing this, you will pretty much always have to do so with the modular units.

Once you have the safety and pistol grip reinstalled you simply go and shoot the gun. You don’t have to set up any adjustments (while some, notably the Timney unit, have adjustments, they are treated just like on the JP trigger, as set ups only; you don’t mess with them).

One of the original ideas was that if you had only one lower and you used it for two very different things, such as self-defense and varmint hunting, you could have two modular trigger units, one with a low pull weight for vaporizing rodents, and one with a pull weight more suitable for shooting Commies. Full brutal honesty took over and you don’t see that marketing much anymore, if only because the average AR owner typically winds up buying a second rifle for the second task. There’s not much validity in that marketing point anymore, as a result of this.

There are only two minor drawbacks to the modular trigger, since the cost in my opinion greatly offsets the installation time and hassle.

The first is that only some of them have some means of immobilizing them in the lower receiver. The ones that don’t place some sort of tension from the housing to the receiver, and will exhibit play that takes away from the quality of the trigger pull feel.

Emplacing a modular unit is child’s play compared to installing one of the non-modular units and is quick and simple, if somewhat more expensive at times.
Emplacing a modular unit is child’s play compared to installing one of the non-modular units and is quick and simple, if somewhat more expensive at times.

The other is that no modular trigger currently made can get to be quite as nice as the single install non-modular units, because each module is designed as a one-size-fits-all assembly. From a gunsmith perspective this is a big deal, but from a consumer perspective it really isn’t all that bad. The modular trigger pulls, like the non-modular units, are so far above the standard factory models in performance and feel that there’s no point in even comparing them to those antiquated, inferior things.

So after free floating your barrel and handguards, the next thing I’d recommend greatly is installing a match grade trigger. Just make sure you take the time to get used to the vastly improved trigger pull.

It’s not unusual for someone who is used to the factory stuff to finger bounce a match trigger, just because it is so much more refined. This is a good time to remember to keep your finger off the trigger until you are ready to fire, and then be in for a world of goodness when you have a crisp, light, quality trigger release.

This article is an excerpt from Gun Digest Guide to Customizing Your AR-15.

Handgun Review: Boberg XR9-S

Boberg XR9-S Review.

The Boberg XR9-S looks kind of funny. The ejection port is situated rearward and the magazine looks backwards. But when you understand how it works, you realize this thing is the ideal concealed carry handgun.

Boberg XR9 Review

Unusual on first glance but the rearward ejection port and the magazine position allow the XR9-S to be smaller than other pistols of similar calibers.
Unusual on first glance but the rearward ejection port and the magazine position allow the XR9-S to be smaller than other pistols of similar calibers.

The pistol uses a pair of tongs (seriously, that’s what they’re called) to pull the top round from the mag, move it up in place behind the chamber, and that’s where the slide starts to move forward to push it into the chamber.

A clever extension across the ejection port keeps the cartridge from popping completely out, and when the slide closes, the tongs drop back down to grasp another round from the magazine.

Here’s the beauty of this design: since the chamber is right on top of the magazine, a full 3-inch barrel can be mounted with the overall length much shorter than comparably chambered and barreled pistols.

For example, this pistol closely approximates a Kahr CW9 type of firearm in chambering, barrel length and capacity, but is just a hair lighter.

Yet it is so much shorter in length and height it’s kind of frightening, being only 5.1 inches long. Placed next to a Glock 26, you would swear it’s a .380 if you knew no better.

It is thin, just under an inch wide, and just over 4 inches in height. Even so, short people with skinny fingers can still actually get all three fingers on the grip below the trigger guard. It’s truly amazing how much difference getting your pinky finger on the grip can be.

Its mass is reassuring, aiding in recoil control, and doesn’t feel like a steel slide atop a weightless frame like many polymer-framed pistols exhibit.

Note the location of the ejection port. It’s over the magazine, not in front of it, while the muzzle actually sits above the front of the trigger guard. for a truly compact, ingenious design.
Note the location of the ejection port. It’s over the magazine, not in front of it, while the muzzle actually sits above the front of the trigger guard. for a truly compact, ingenious design.

Daintily fingered folks should have no problem controlling the XR9-S because of this. It’s double action only, but the pull is extremely smooth, repeatable, with a long reset and decent weight for safety considerations.

The gunsmith in me has to make the following observations. It appears really complicated when you first look at it, but it really isn’t so much.

There are around 50 parts in the entire gun, which isn’t bad. Generally, the fewer parts you have the better for maintenance’s sake, and after sticking my fingers in it, I found that it’s not overly complicated or difficult to service.

Its appearance at first glance (and knowing how it feeds) leads one to assume a certain case of Teutonically inspired over-engineering might be involved, but I was pleased to see that this was not so.

Recoil mitigation is also consciously present by means of semi-flexible plastic grips, which are wrapped around the machined aluminum frame, a rotating barrel housed within a stainless steel slide, a rear buffer and a couple other harder to describe things that I can’t remember cause I was distracted trying to contain my drool with one hand, while keeping the product free from contamination with the other. (Hey man, I can only do two things at one time.)

My only complaint is that because of the design with the barrel set back, there is no traditional slide stop. The slide can be easily locked back manually using the takedown lever, but some purist 1911 trolls will likely take exception to the absence of the last round lock back. On a deep conceal pistol, which this qualifies to be in my opinion, it’s not that big a deal.

Boberg XR9-S.

Care and Feeding

Boberg XR9-S magazine.I should note that the means of feeding has resulted in a new failure type, not experienced by other common auto pistols.

If the cartridges do not have a strong bullet crimp, the bullet will remain in the magazine when the tongs pull the case from the magazine for feeding.

Fortunately, this situation is limited to a few cheap ammo types and that information is included with the manual and also on the web site at bobergarms.com.

Decent self-defense ammo, like that used by just about every serious shooter carrying a pistol, will not be a problem.

I test fired with Winchester white box FMJ and Federal Hydra-Shoks and had no issues. I tested only for self-defense accuracy. I set the target to 7 yards and fired with only my strong hand in a not quite rushed five-shot string, in very, very subdued lighting. I believe it to be fully acceptable in the accuracy department.

Holsters are available, and I would advise against, using the cheap $10 sheath type one-size fits most numbered holsters.

Those no-retention, thin polyester sheaths rely on longer projecting barrels and belt tension to hold the pistol securely, and the setback barrel on the XR9-S will not work so well with those.

There are over 20 holster makers fitting leather and Kydex for the XR9 series and one of those quality products should be obtained.

Boberg Arms is just barely keeping up with demand, and as of this writing, the XR9-S is only available through the manufacturer and a few approved dealers. The MSRP starts at $995.

This article appeared in the March 25, 2013 issue of Gun Digest the Magazine.

Building a National Match AR

How to build a National match AR

The author builds a National Match AR from parts to be used in CMP competition.

A year or two ago I decided to try some three-gunning. For those unfamiliar with three-gun competition, it is essentially a type of match where the competitor uses a rifle, pistol, and shotgun, in multiple and combined stages, and operates under time and scoring constraints, plus whatever the sick, sick planners of the stages decide to insert into the course.

It’s a lot of fun, and can be very challenging, however it also has a very high round count, as in hundreds and hundreds, and requires three guns, which can be pretty inexpensive, but can also be very not inexpensive. I decided that I wasn’t quite ready for that, but I still wanted to shoot ARs in some sort of competition setting.

The JP adjustable gas block has a set screw to allow the user to tune the gas system. Just make sure the Loctite is set before you shoot, or it will blow out around the screw like in this picture. Note also, where the author made the slight modifications to the handguard swivel attachment point, and to the bottom rear of the sight's rear clamp to allow the incompatible to become compatible.
The JP adjustable gas block has a set screw to allow the user to tune the gas system. Just make sure the Loctite is set before you shoot, or it will blow out around the screw like in this picture. Note also, where the author made the slight modifications to the handguard swivel attachment point, and to the bottom rear of the sight's rear clamp to allow the incompatible to become compatible.

What I settled on was to shoot CMP sanctioned matches using the General Service Rifle rules. Now, I’m not going to go into the details of this type of match, simply for lack of room, but I will relay a couple of hints. In a nutshell, you need a 20-inch AR-15 with a carry handle. On the exterior it must remain orthodox in appearance, with the aforementioned 20-inch barrel, standard handguard, carry handle, standard military sights, standard pistol grip and stock, etc.

There are minor modifications to the exterior allowed, such as a non-threaded barrel with no muzzle attachment, a detachable carry handle, a stainless steel higher quality barrel, a free float tube that uses the standard handguard halves, several different minor but useful sight modifications (such as a corrective lens or finer adjustments), and the ability to use pretty much any color you want for the stocks if you want to be something of an individual. There are also a few must-have criteria that will be mentioned in italics as we progress.

Most large AR manufacturers such as Colt, Rock River Arms, and DPMS offer purpose-built models for this type of competition and generally they are quite good at it. However, I am loathe to simply buy a complete ready-to-use product, so I decided to go a little further and build my own from parts.

Fortunately, Brownells was able to offer most of what I needed. With all the insanity of the AR market with its super special aftermarket stocks, pistol grips, and doo-dads of whatever persuasion there is still the good old inexpensive A2 stock and pistol grip, which are required by the rules. These came from Brownells with no hassle, and included the receiver extension tube (buffer tube for you non-purists), buffer and spring. Truthfully, I can’t stand the A2 pistol grip, mostly because of the finger groove on the front of it. The little projection is entirely in the wrong place for my small hands, and ironically the grip itself feels too skinny, probably because I’m used to using MagPul pistol grips. Well that’s tough since my choices are A2 or A1 grips, and since the rest of the rifle is A2 configured, I reckoned that putting an A1 grip (without the finger rest) would just look stupid.

Also from Brownells was the NM free-float tube made by Rock River. Most shooters can sling up a rifle so tight on a front-sight-mounted sling that it affects the point of impact. And probably no shooter can sling up in a sufficiently repeatable fashion to affect that point of impact the same exact way twice. So the handguard, in addition to being free-floating, also has a sling swivel on the front/bottom of the inner tube, thus transplanting the sling-up stress to the tube rather than the barrel. This makes this tube much superior to the standard handguard for accuracy, but also makes it substantially heavier, since it’s made of steel. Most competitors don’t mind that weight since it helps to keep the entire rifle more stabilized.

The barrel configuration purchased from JP Enterprises came with an A2 style front sight adjustable gas block. The author then installed a match front sight post from Brownells. The special gas tube from the free float handguard has also been installed.
The barrel configuration purchased from JP Enterprises came with an A2 style front sight adjustable gas block. The author then installed a match front sight post from Brownells. The special gas tube from the free float handguard has also been installed.

Barrel

The heart of a rifle is its barrel. Having had great experience with the barrel kit I purchased for a three-gun rifle, I again tried a barrel kit from JP Enterprises. I ordered one of their 20-inch barrels, modified. As standard, it takes a .936” gas block over a .875” barrel. I had them turn the barrel down to take a .750” gas block, thus the same required contour past the handguards as a standard M-16/AR-15 20-inch barrel. To this barrel was attached one of their A2 front sight posts, called a JPGS-2FS. It clamps on, rather than pinning, similarly to the windage adjustable gas blocks the larger companies use, has an adjustable gas system, and closely duplicates the standard front sight tower. This set screw allows the shooter to tune the gas system to any particular ammo, yet the gas system remains fully functional, as rules require.

The potential downside is the resulting lightness of the barrel, which kind of bucks the current in a sport where heavy contoured (behind the gas block) barrels are the norm. However, upon completion of this project I found that the rifle’s balance was absolutely perfect in my eyes and was very easy to hold for extended periods gazing through the sights.

The front sight post was also a match type sight procured from Brownells, thinner in cross section than the standard front sight post. An Armalite National Match rear sight from Brownells replaced the standard sight on the carry handle and was the most annoying thing to install. Don’t lose the ball bearings, and be sure to use your third hand, since you will need it.

To spread things around a bit, I ordered the removable carry handle from Del-Ton. Why? It was a quality part (there are a lot of crappy carry handles out there) for a very reasonable price, and I have always liked Del-Ton’s customer service, prices, and item selection, which make it an obvious place to find things I need.

I was forced to make a modification to the handguard and front sight/gas block, which is befitting a gunsmith building a rifle. I milled off a radius from the top corner of the swivel loop on the handguard, and ground off a small amount from the back of the rear gas block clamp so they could fit together on the barrel without interfering with one another. The accompanying image shows where the two parts were affected.

JP's Lower with Trigger, the smart man's module. Set up to your desired trigger weight range, it bears a cost similar to many modular trigger sets, yet provides an entire lower receiver to boot.
JP's Lower with Trigger, the smart man's module. Set up to your desired trigger weight range, it bears a cost similar to many modular trigger sets, yet provides an entire lower receiver to boot.

Lower

Real quickly, when I was ordering the barrel kit, JP’s “modular” trigger caught my eye. Not a modular trigger at all in the traditional sense, it is simply JP’s standard single-stage match trigger installed in a stripped lower receiver, for $350, and correctly called a “Lower With Trigger.” Frankly, I haven’t met a modular trigger that I really liked; they all have their little idiosyncrasies and while good, can’t ever seem to quite stand up to a dedicated non-modular type standard match trigger.

So, I thought that $350 was quite a decent deal for a stripped lower with a match trigger kit, set up for the 4.5 pound minimum pull weight. I removed the anti-walk pins to replace them with standard trigger and hammer pins. Onto this lower receiver went a lower parts kit that I had sitting around and the stock and pistol grip from Brownells. I also dug up an old standard aluminum 20-round magazine (that I know still works well) that probably went to Vietnam and back to feed the rifle. Standard 30 round mags are okay too, but shooters often monopod on them during prone strings of fire.

Testing

While using the same handguard plastic halves, this kind of rifle retains them in a steel tube assembly that just looks like a standard handguard, without touching the barrel, removing stresses, and making the barrel more accurate. Incidentally, the bend in the gas tube is also moved forward to better accommodate the steel tube.
While using the same handguard plastic halves, this kind of rifle retains them in a steel tube assembly that just looks like a standard handguard, without touching the barrel, removing stresses, and making the barrel more accurate. Incidentally, the bend in the gas tube is also moved forward to better accommodate the steel tube.

While I need to get outside more and practice, it was a non-problem for me to take a quick trip to the indoor 50-yard range to break this rifle in. The best groups I got were with American Eagle 55-grain FMJ ammo, both under ½ an inch in this setting. Theoretically, on a calm day at 100 yards I should get under an inch, and for my first CMP rifle, I’m totally satisfied with that result. Felt recoil was ridiculously light, due to the adjustable gas system and the low-mass bolt carrier that I also purchased from JP. Most felt recoil in an AR is from the mass of the buffer and carrier group hitting the back of the stock. By lightening that load somewhat, and reducing the tuning, the gas needed to operate the rifle with the adjustable gas block, most of that felt recoil can be eliminated. Most rifles are over gassed for reliability, but adjustable gas blocks allow you to tap off only what you need, not what the manufacturer thinks you may someday need on the surface of Mars. This should allow me to get the sights back on target faster during the rapid-fire stages of the matches, hopefully giving a slight boost to performance.

Conclusion

My goal was to build a gun for the National Matches and I did so. Yes it cost me more in the end than buying one off the shelf, but I got a rifle that was mine, not someone else’s. And since the CMP rules allow detachable carry handles, I can take my carry handle off and use the rifle with an optic for some other task, such as hunting, or another shooting sport, as I see fit, and then simply replace the carry handle for my next CMP match. I am a believer in versatility and this rifle meets that description.

By spending a little extra on premium parts, you can still make it out the door under $1500 (less than your average piston operated AR carbine) and you should have a demonstrably better rifle, personalized, than a mass-produced off-the-shelf version of the same thing.

Since people are probably getting sick of me writing about ARs (even though that market is hot) we will next be moving back into some traditional detailed gunsmithing for the next few months. Till then, find a sport and shoot it.

This article appeared in the July 4, 2011 issue of Gun Digest the Magazine.

Gunsmithing: Can You Improve the M-1 Carbine?

The stock and rail are installed and the wood is showing off its grain a bit.
The stock and rail are installed and the wood is showing off its grain a bit.

While the M-1 Carbine has been denigrated for lack of stopping power and inaccuracy, it has a lot going for it and, yes, it can even be improved.

Long a favorite of mine, the old M-1 is a favorite of many others, too. Except for gun writers, who seem to hate the thing. This hatred is caused, in my opinion, by a lack of modern ammo development and, I think, a bit of snobbery. Long has the Carbine been denigrated for lack of stopping power, inaccuracy, and an anthropomorphic lack of small round things.

This has always bugged me, because as a short little half-Asian kid in the COLD swamps of Wisconsin, a better deer rifle could not have been found. So, I have traded my uncle’s collectible Winchester for my somewhat beat up CMP Inland. Of course, before long the gunsmith’s curse, the desire to spiff it up became too great.

An image from the rear quarter shows the whole assembly, rail, stock, and dot
An image from the rear quarter shows the whole assembly, rail, stock, and dot.

Did You Ruin a Historic Piece?

So what can be done? I didn’t want the “sporterizing” or butchering like so many of these rifles have been subjected to, but I wanted it to be nicer than it was. This carbine languished in some dank linguini warehouse in Italy for the last 40 or 50 years and the stock looked it, with lots of grease and oil stuck in it. The surface was splintery and otherwise generally rough. The solution to this problem was a new stock, which I ordered from Fulton Armory in Maryland.

This was a brand new walnut stock cut with precision. There was only one thing that did not fit perfectly and it shouldn’t be expected to. The wood surrounding the recoil plate at the back of the receiver stood quite proud, but that was to be expected. In all other areas the stock and handguard fit perfectly and that was in a word, suh-weet. There was also no need to prepare it, as it had already been fully shaped and sanded. I was very pleased with this stock and highly recommend it for replacement or upgrades.

To the accurizing. Referencing The U.S. .30 Caliber Gas Operated Carbines: A Shop Manual by Jerry Kuhnhausen had already proven useful for function and safety checking the rifle. Now the small accurizing section at the back was used to give this humble columnist a clue. Also referenced was the Civilian Marksmanship Program’s website (www.thecmp.org) where a link to accurizing M-1 carbines resides.

There was little disparity of import tween the two, and they said, in a nutshell, the recoil pad needed to be securely bedded, as did a spot under the barrel at the front of the stock. Clint McKee from Fulton Armory was also a wealth of information.

Beginning the Work

The Vanderhave formula stain allowed the author to (in his humble opinion) do a superb job duplicating the reddish color of the original walnut stock.
The Vanderhave formula stain allowed the author to (in his humble opinion) do a superb job duplicating the reddish color of the original walnut stock.

Using a vertical mill, I removed wood from under the recoil plate and around it, leaving a very slight shelf around the edge of the screw hole area for locating purposes. To fashion a tube for the recoil plate’s screw (so as no bedding contacted it), I cut and unrolled the rolled aluminum handle of one of the acid brushes in the Brownells bedding kit, then re-rolled it around the recoil plate screw, and then cut to size.

I then inserted this resulting tube into the hole in the stock and the bedding compound was then applied around it. (I bet Brownells didn’t see that one coming). The recoil plate, thoroughly coated with release agent was then smushed into the bedding compound and seated on that little locater shelf left behind. Of course the compound proceeded to ooze about and the stock around the recoil plate then needed some cleanup.

I then inserted the action in the stock in order to insure that the recoil plate was properly aligned straight ahead, and tightened the screw. Once the compound was sufficiently set, the action, and then the recoil plate were removed to allow the compound to finish hardening.

I next dug out a small channel just behind where the inner fingers of the barrel band wrap around the barrel at the front of the stock. The Kuhnhausen manual indicated placing the front bedding pad under these fingers but I didn’t want to mess with that so I placed this bedding pad just behind them. I figured since the pad was just about in the same place, its function being to provide a secure base for the barrel, that it should work out just as well a half inch displaced.

Next was to modify if necessary the recoil plate, so that it caused the barrel to sit slightly high above the forend pad, thus causing a certain small amount of constant tension to be placed on the barrel when the barrel band was installed. Fortunately, there was about 1/8 of an inch of float there inherently, so I decided to leave it be and not attempt to add more.

The last step was to stain the stock with the Vanderhave formula XIII from Brownells. This stuff is supposed to duplicate the dark, slightly reddish color of the old WWII stocks. I thinned it out a little using alcohol and used an old, yet still white, sock to apply it to the wood.

I rubbed in a rather dilute coat to act as a sealer and a less dilute coat to actually stain the stock and handguard. Following up, two nice coats of tung oil were rubbed in and the stock sat for a few days before I used a 1000-grit piece of sandpaper to lightly take the shine off the top coat of tung oil. Lo and behold, it looked pretty darned good, having a slight reddishness and being just a teensy shade lighter than the oil-saturated stock the carbine came in.

The new stock on the left and the old on the right, seen post bedding and finishing.
The new stock on the left and the old on the right, seen post bedding and finishing.

The final piece of the equipment upgrade was to add a scout rail, which replaces the handguard. This rail was made by Ultimak and obtained from Brownells.

This handy rail directly replaces the handguard with an aluminum section topped with a Picatinny rail. All sorts of stuff can be added here, like a scout style extended eye relief scope, but I just put on a cheap, little micro-red dot sight. It should be noted that installing anything onto this rail will remove the iron sights from play, and anything placed there may wind up getting rather warm from heat transfer off the barrel. Then it was off to the range.

Range Report

I test fired for groups prior to the upgrades and with my somewhat poor abilities got roughly 3-inch groups at 50 yards, shooting 10-round groups. Not five. Not three. Anyone pawning off five-shot groups and calling them representative is telling fish stories. Anyone using three-shot groups, or best three of five, is flat out lying to you, pulling fabrications from a certain posterior fissure. The more shots, the better, and 10 or more shots will open up a bit from 5 shots, hence the reason gun writers and manufacturers like to use five-shot groups, but it just isn’t a valid scientific representation.

The 10-shot group is little better, but the difference between a 10-shot and a 20-shot is almost always far smaller than the difference between a five and a 10.

Post upgrade, the best group I had was nine shots out of 10 in a 1-inch ragged hole, with the tenth another inch away, a “flyer” if you will. Still, a 2-inch 10-shot group is a lot better than a 3-inch 10-shot group.

All post-upgrade groups shot at least slightly smaller than pre-upgrade. Reloads from Wisconsin Cartridge Corporation, and factory Remington UMC were used, with the UMC getting the best groups. Incidentally, I also loaded up some Barnes 100-grain X-bullets (no longer available) and they shot pretty crappy. Six inch group. I really hope it was poor reloading technique.

This article appeared in the February 14, 2011 issue of Gun Digest the Magazine

Gunsmithing: Little Tools Are the Basis of the Shop

Gunsmith Tools
Buy them both. Magna-tips on the left and Wheeler Engineering on the right. One for the bench and one for the range.

As your humble author was working on this column, it occurred to him that he, long ago, wrote a similar article for this publication. But that’s okay, ‘cuz this one’s better. This month, we want to briefly discuss the tools that the new gunsmith should shell out the initial dough to purchase, and those that he can or may be able to do without. As such, there really aren’t a whole lot of these initial tools, so they will be broken down by section below, with recommendations based upon personal use.

Unfortunately, common tools, like standard screwdrivers, pliers, hammers, and the like have limited use on the bench of the gunsmith. For gross (as in large, not as in yucky) operations they work well, but they are not necessarily suited to the precision work demanded when working on guns. Likewise, fine precision tools like those used in the electronics industry, while great for fine control of springs and pins and stuff, simply aren’t tough enough to last for long under the heavy-handed abuse of the average overweight, under-exercised gunsmith. Fortunately there is a thriving special industry of overpriced (sometimes), overbuilt (often), and convenient (always) tools for dudes to blow their paychecks on.

Hammers

Gunsmith Tools
Here are the four slammers the smith will need for 99% of his slamming.

You will need a hammer or four. The first is the most used and thus the most important and essential smasher to acquire. Brownells has a great model that is simply adorable, a 1-inch nylon/brass headed item, weighing about 6 ounces. You will use it every day, and it is the most suited for the most common punching and driving of small pins and parts that you will encounter.

It will wear down and require dressing, the brass head will expand and need to be pounded or turned back into shape, and the nylon head will start to look like it went on a date with a cheese grater. If you can get spare heads, do it. Eventually it will expire and you will be forced to get a new one. Strangely, it is a very inexpensive replacement. For as much as it is used, Brownells should double the price and really make it profitable.

Buy a rubber deadblow hammer for heavier soft work. This is your second hammer.

The third hammer to get right away is a heavier steel model. Many smiths use a standard ball-peen hammer to help loosen those hard-to-move super-tight pins. The typical gunsmith’s tool bench is the home to a 1-pound steel that is quite easy to control and has the necessary mass to overcome all but the most stubborn interference-fit inertia.

The old adage, “Don’t hit it harder, use a bigger hammer,” is oh-so-true in Gunsmithtown. The harder you hit something, the less control you have, and inevitably you will ruin your tools and the piece you are working on. You know, the workpiece that belongs to someone else.

Overcoming inertia requires force. Force is applied with a hammer using speed or mass. Mass is easier to control and far more effective, hence the 1-pound hammer for moving the tapered front sight pins on an AR. Which brings us to the fourth hammer … the Hammer of the Gods. Thor called his “Mjolnir.” I call mine Pickles. Use the 16-pound sledge hammer to beat the ever-living crap out of that old .22 from the thirties that has no value, doesn’t function, and continues to reside in your shop for the sole purpose of relieving frustration. Plus, its effect on box elder bugs has to be seen to be believed.

Screwdrivers

Buy the Magna-tip 58-bit Master Super set, and the thin bits sets from Brownells. Use these for your bench. Very, very high quality tools. If you want a range set to allow you to show off your sexy gunsmithin’ to the hot chicks at the range, buy the Wheeler Engineering 89-piece set from Midway USA. It has several specialty bits that turn three-handed 15-minute jobs into two-handed three-minute jobs.

Punches

Discount sets have their place. But not in the gunsmith shop. Great success has been gained with Starrett punches from Brownells. Also get roll pin punches and those cute little hollow-nosed pin starter punches.

Other Stuff

Gunsmith Tools
Polish, polish away. A high speed rotary tool will make you a very happy little tinkerer. Just use it with control and intention. It can also pave your pathway to abject failure and doom.

Get a high quality Dremel type tool. I’ve yet to find one that will stand up to hard use, most being of the hobbying variety. Be prepared to replace this one yearly. Once you have one, though, it is hard to get along without. For some unknown reason, motors and electricity have this funny way of making work easier. You will use this for grinding, polishing, buffing, hogging out stocks for glass bedding, and who knows what else.

A variety of hand files are a must. The models available at your local home supply store are generally of adequate quality, as long as they are the expensive ones. Large bastards, mills, and the little needle files are all needed.

Ceramic or Arkansas polishing stones are essential for trigger work and other fine material removal.

One interesting and miniscule tool to acquire, or make, is a firing pin protrusion gauge. You may not actually need this one right away, but you will need it eventually. Worn firing pins, or badly manufactured firing pins, will cause headaches and this little doozy will help you figure out if either is the case. This tends to be needed on older guns with heavy mileage, and there are a whole lot of those out there.

Get several sets hex wrenches. Preferably ball ended. Without a doubt, get metrics. You’ll need those to handle all those crappy ChiCom red dot sights that are flooding the market. Invaluable tools, they are must haves; and be prepared to order extras after you lose or break a few.

Finally, at the risk of alienating all those manufacturers in the ether of Gunsmithtown, most of the jigs, rigs, and nice-to-have gadgets are not really necessary for immediate accumulation. That’s not to say they are useless, because they are often very handy and make the job more efficient. They just tend to be pricey, and the average dude should put off getting them until he knows he will get his money’s worth.

Lube and Cleaner

Gunsmith Tools
Commonly found solvents and lubes, and a couple greases. All have their purposes in the workings of a firearm, and all work at least reasonably well. The perfect lubricant and the perfect solvent have yet to be discovered.

It would be a good idea to get a parts cleaner, and maybe a small ultrasonic tank. Overall, you may find that your selections of bore cleaners, lubricants, and the like will be determined by your nose, or specialty. A lot of guys get positively high off of Hoppe’s #9, which is okay since it works quite well, and you might as well enjoy your work. Some people think its odor is too strong. Well too bad for them. They may then gravitate toward Tetra’s line of cleaners and lubes, which have a completely different aroma.

Fortunately, the great majority of the cleaning solvents and oils in Gunville are reasonably or greatly effective at the tasks for which they were produced. However, my experience with the “green” environmentally friendly, non-toxic selections has been disappointing. If I can drink it and not die, it has no business touching my guns. Gun solvents should be like coffee: great to smell, but revolting in taste, and capable of stripping copper from barrels, and cells from esophageal linings with equal ease.

Conclusion

All of this stuff can be purchased for well under 10 C-bills. Between these tools and those discussed in next month’s column, the new-born gunsmith can accomplish the vast majority of the everyday jobs. And this shouldn’t put him out too much dough if it turns out not to be his cup of tea. A lot of guys just do this kind of thing casually, fewer as a career, and many others try it and change their minds. Starting out small and wise like this will absolutely benefit anyone.

This article appeared in the April 12, 2010 issue of Gun Digest the Magazine.

Build an AR from Scratch – Part IV

Completed, the pair of ARs sits happily on mother-in-law’s kitchen table. Note the eye catching contrast of the FailZero treated receiver with the rest of the black rifle. The author is all about good looks.
Completed, the pair of ARs sits happily on mother-in-law’s kitchen table. Note the eye catching contrast of the FailZero treated receiver with the rest of the black rifle. The author is all about good looks.

Installing the fire control is easy. Stick the safety/selector in from the left side and turn the receiver upside down on the vise block. Drop the detent in its hole. Place the selector detent spring into the small hole on the top of the pistol grip, hold it there with the tip of your finger and put the pistol grip onto the receiver, then hold it while you fiddle one handed with the grip screw.

I can’t figure why everybody insists on using a stainless steel flathead screw here, instead of an alloy socket head. Must be “mil-spec.” Take your guide tool (firing pin with tip cut off) and use it as a slave/guide pin for the hammer and trigger. Install the trigger first, without the disconnector. Drop the trigger in and insert the guide tool in from the left and all the way through. Push the trigger pin in from the right, all the way through.

Do the same for the hammer; and you may have to gently tap the hammer pin in. Then push the trigger pin a little more than halfway out and insert the disconnector into its slot in the trigger, hold it with the guide tool, and push the pin back all the way back through. This little guide tool will save you many number 10 frustrations.

The economy rifle, complete with favored accessories – MagPul Pmags, shooting glasses, Surefire Sonic Defender earplugs, and OTIS Tactical cleaning kit. All that is now needed is a pony and tactical mane comber.
The economy rifle, complete with favored accessories – MagPul Pmags, shooting glasses, Surefire Sonic Defender earplugs, and OTIS Tactical cleaning kit. All that is now needed is a pony and tactical mane comber.

Test the function by cocking, “firing” and recocking again without releasing the trigger. The hammer should be retained by the disconnector and should reset with an audible clack when the trigger is released. Do this multiple times. The hammer should not fall upon trigger release, though that may happen when the disconnector gets worn after extensive use. The safety should engage and prevent trigger pull beyond a little take up. The take up should reset upon trigger release. If this all works, slap the upper onto the lower, and repeat the fire control test while cycling the bolt. If it’s still okay, you are done. For best results apply a dab of grease to the sear/hammer surfaces, the slots in the takedown and pivot pins and selector.

Shameless Promotion

The go-to carbine was finished off with a DPMS detachable rear sight that was in my pack rat box. There is now before my eyes a basic, quality utility carbine. Add a PMag and it’s heaven on earth. This is now my house gun.

We haven’t really covered the hunting rifle, since it was my intent to get constructive descriptive only on the run of the mill assembly, which the hunting rifle really was not.

With the wife’s permission, an 18-inch 6.5 Grendel CTR upper, black barrel, with scope mount and two 10-round mags, were ordered from JP Enterprises. I then promptly tore it apart and sent some of it off to FailZero (www.failzero.com). These dudes apply an electro-less Nickel-Boron-Nitride plating, called EXO Technology, to the receiver, charging handle, hammer, and bolt carrier group. It is billed as a lubrication-free coating, and after hundreds of hand cyclings and dozens of actual shots, seems to be just as advertised.

So far there hasn’t been any flaking or chipping, or malfs. While there does appear to be a slight polishing on the bearing surfaces, that is actually a bonus, operating even more smoothly. Furthermore, it has a nice “Leupold silver” color that really looks fine on the black rifle. I figured that a deer rifle used in below freezing weather might just benefit from a lube-free nature, since many common gun oils don’t hold up so well in those conditions, and can freeze or gum up, counteracting their very purpose.

6.5 Grendel vs. .223 Remington. As can be seen the Grendel uses a significantly fatter cartridge, with a much longer bullet. Grendel mags are black stainless steel, while the .223 on the right stands before the vaunted Pmag.
6.5 Grendel vs. .223 Remington. As can be seen the Grendel uses a significantly fatter cartridge, with a much longer bullet. Grendel mags are black stainless steel, while the .223 on the right stands before the vaunted Pmag.

FailZero also offers kits of their own, one of which includes bolt carrier assembly, hammer, upper, and charging handle, in bare or black. I suspect that it would also be of great use in a talc-dusty environment like where our servicemen are shooting bad people. There are also a couple of fascinating (really) scientific papers describing the process linked to their website, explaining its superiority to hard chrome or other electro-less platings currently on the market.

Finishing off the hunting rifle was a Rock River Arms Match trigger (also from my pack rat box), a Badger Ordnance Gen II Tactical latch and ACE ARFX skeleton stock from Brownells, and my trusty, much used Zeiss Conquest 3-9×40 beat up test scope.

The RRA trigger is a nice set. It is smooth and crisp. As with the economy rifle, a dab of grease was slapped on the sear/hammer interface, and disconnector/hammer interface. There are some folks out there who say that is a bad idea, and can cause malfunctions. But it’s my experience that if a gun’s fire control malfunctions (fires on release, fails to disconnect, doubles, etc) it will do so whether there is any grease there or not. Greasing this used fire control set made it slicker than snot on an August afternoon.

The Gen II tactical latch is extended longer than a standard latch, but not nearly as protrusive as the original tac latch. Both are rather appealing, but since this rifle was going to be carried in the woods, your esteemed author didn’t really want a huge latch digging a new navel in his torso. The Gen II latch is just large enough to be obscenely useful, but not so big to be a nuisance.

The ARFX stock, another one of my favorites, is a lightweight, low profile stock. The best part about it is the foam covering the buffer tube, making the -10 degree cheek-weld a rapturous delight.

Conclusion

I’m happy with the set up; it shoots well under an inch at 100 yards, factory and reloads. The ballistics of the 6.5 Grendel cartridge are impressive and can be examined at the website of Alexander Arms (www.alexanderarms.com), the originators of the cartridge.

It shoots very flat, most bullets having very high ballistic coefficients. Even out of short barrels, it still retains enough velocity in 100- to 123-grain bullets to be supersonic past 1000 yards. Yet it is light recoiling, and the available bullet selection for reloading is large enough to waste some few hours tinkering with loads. It stands a chance of becoming my chosen all-around pick, for practicing long-distance stuff, to mid range steel, to close range Bambi carnage.

Value describes all the ingredients in these two recipes, value in thrift and in largess. The greater value is in building rifles with your own two hands, to the design that only you can perfectly derive, for the purposes only you can conceive, on those two hundred dollar chunks of machined aluminum that you bought for a rainy day.

This article appeared in the March 15, 2010 issue of Gun Digest the Magazine. Click here to load up on your subscription.


custom-ar

Gun Digest Guide to Customizing Your AR-15

You’ll appreciate this AR-15 book if:

  • You want to learn how to customize an AR-15
  • You need help sorting through the nearly endless array of AR accessories
  • You’re looking for inspiration for your own AR-15 customization

Build an AR from Scratch – Part III

Holding the detent in like so will allow the other hand to use the pivot pin to push the detent fully into the hole, allowing the pin to move left into its loops, also retaining the detent underneath.
Holding the detent in like so will allow the other hand to use the pivot pin to push the detent fully into the hole, allowing the pin to move left into its loops, also retaining the detent underneath.

Today’s lesson begins with a short recap. In the last two installments of this column we have been building an inexpensive go-to rifle and a not so inexpensive hunting rifle.

The lower receivers were supplied by C3 Defense (www.c3defenseinc.com), while the remainder of the go-to rifle was a 16” carbine kit from Del-Ton. The other stuff for the hunting rifle will be detailed in a later paragraph.

ARPart3-2-375.jpg

The next step was to assemble the lower receiver of the Del-Ton/C3 rifle to complete the carbine. The steps below are not necessarily the most comprehensive, but rather are an attempt to make the steps easier from my own extensive AR construction experience, in an order absolutely guaranteed to prove the most convenient and happy-happy for you.

This also assumes that the reader who attempts this type of build is also more intelligent than the average arboreal primate.

To begin, pins such as the trigger guard pin are easier to insert if you push or pinch them in, rather than tapping. The trigger guard ears are easily broken from pounding, so if you have a bench vise with hard flat jaws, the pin can be easily and cleanly fully inserted by slowly closing the vise jaws on a pin that has been finger pushed or “tap started” in the hole.

This should be the first step. Our second step is to screw in the magazine catch. The tip here is to grab your firing pin and use the back end of it to push in the mag button from the right side (with spring inserted first, of course), and screw the latch itself until the tip of the screw becomes flush or just below flush to the outside surface of the button.

The firing pin will allow you to push the mag button all the way in, allowing the latch to screw in the necessary amount while still clearing the left side of the receiver. Unless you are a lefty it is this author’s recommendation to stay away from the ambidextrous magazine catches. Norgon makes a truly wonderful model but it tends to be pricey, and is not worth it for a righty.

However, if you are a lefty, it is almost a necessity, and according to the mutant dominance-challenged lefties that I have talked to, it is the finest accessory available. The third step is to install the bolt catch. Use a roll pin starter punch of the appropriate size and tap the latch retaining roll pin in (standard forged receivers from the front; however, most billet machined lowers like these from C3 Defense, almost always require installation from the rear) until its leading edge is flush with the inside of the slot within which the catch rotates.

Then insert the spring, detent, and latch, and tap the pin in, while holding the catch in with your third hand. Finish the pin insertion with Brownell’s bolt catch pin punch. This is a handy punch that is flattened on one side to allow left side receiver clearance and simplifies bolt catch installation nicely. It’s long enough to use from the front or the back and is a mere sixteen bucks.

Its purpose is mainly cosmetic, so you don’t scratch up the side of your receiver with a normal knurled punch.

Three very handy tools for this segment are an M4 stock wrench (actually this one is completely necessary), a Brownells bolt catch pin punch, and a firing pin.
Three very handy tools for this segment are an M4 stock wrench (actually this one is completely necessary), a Brownells bolt catch pin punch, and a firing pin.

PINS

Pivot and takedown pins next. If you haven’t got a lower receiver vise block, get one, or use a crappy magazine. Brownells has the former, everyone has the latter. Stick the vise block in the mag well.

Place the receiver in the vise so that the front of the receiver is pointed at the sky. Drop the pivot pin spring in the hole on the right front of the receiver and use needle nose pliers to grasp the detent, pushing it in part way until the pliers prevent any further insertion. Then take the pivot pin with your other hand and push with the side of the nose of the pin straight down while pulling the pliers off.

This pin should push the detent right down flush and then you can just shove the pivot pin into its loops. There is a tool out there somewhere that is supposed to make this task easy but this is one instance where the “nice to have tool” is just not worth the money.

This is merely a simple test of your dexterity, and you should pass as long as you don’t have any kind of the shakes. If you have the shakes then by all means buy the pivot pin installation tool. But since its existence so offends me, you can just go out and find it yourself. The rear takedown pin installation is integral with the installation of the stock.

Some billet receivers out there have a retaining screw for the takedown pin detent spring, but most times the spring is retained by the buttstock. In this case, using an M-4 style stock, the receiver end plate (as Colt calls it, I call it a stock/receiver plate) holds the spring in and the castle nut tightens the plate to the rear of the receiver.

Insert the pin halfway with the slot to the rear and stick the detent in the small hole in the back of the receiver, followed by the spring. Place the buffer detent and spring into the large hole just in front of the receiver threads at the back of the receiver. Screw the castle nut on, notches to rear, then slide the retaining plate onto the buffer tube and apply blue loctite to the threads.

Then screw the extension tube in until the lip on the front of the mouth of the tube retains the buffer detent in the hole. Most combination action wrenches don’t have the right stuff for this castle nut, but the M-4 stock wrench (a cheap 10 bucks usually) is made to order for tightening this nut.

Brownells has a new model of this wrench that engages all four of the notches, and while more expensive, I expect has a significantly longer life expectancy. The front of the castle nut has three little indents in it. Take a punch and stake the rear edge of the plate into one of these indents. One should be enough.

This and the blue loctite should suffice to keep the stock nut tight. One thing to note is that there are two types of collapsible stock extension tubes, commercial and mil-spec.

The mil-spec tube is about thirty thousandths of an inch smaller in diameter. Mil-spec stock pieces will not fit on the commercial tubes, and the commercial stock pieces are so loose on a mil-spec tube that even a moron might think that something is amiss from the persistent high volume rattle.

Fortunately, most, if not all, stocks out there are made in both sizes. This particular tube was of commercial diameter. I’m going to end this installment here. The conclusion, including the fire control installation and the details of the hunter build will be relayed in next month’s column. Till then, have a nice life.

This article appeared in the February 15, 2010 issue of Gun Digest the Magazine. Click here to load up on a subscription.


AR-15 Ready Kit

AR-15 Ready Kit

The AR-15 Ready Kit offers huge savings in this value pack format as opposed to purchasing these components individually – it’s no more expensive than a case of .223 ammo, but will compliment your tactical rifle kit for a lifetime.

Build an AR from Scratch – Part II

0
Using a hard surface as an anvil for the rivet head, one can then use a roll pin punch to expand the rivet tip to secure the sling swivel to the front sight gas block.
Using a hard surface as an anvil for the rivet head, one can then use a roll pin punch to expand the rivet tip to secure the sling swivel to the front sight gas block.

When last we spoke, the examination of the two lower receivers from C3 Defense (www.c3defenseinc.com) had concluded and we had initiated the construction of the upper receiver for the economy rifle, with all the remaining parts from Del-Ton, Inc. (www.del-ton.com).

Having the completed upper in hand, we move on to installing the barrel. Make sure the upper receiver threads and the threads of the nut are completely clean and free of foreign objects, like burrs, dirt, grease, or blood.

BARREL

The most difficult chore here is to install the snap ring on the delta ring. While not absolutely required, snap ring pliers are very, very useful here. The barrel should have the serrated barrel nut already installed. Place the large angled aluminum delta ring around the rear of the barrel nut, with the small diameter facing forward.

The large weld spring can then be placed against the rear of the angled ring. The split snap ring is then placed on the nut and pushed home into the groove on the barrel nut. This compresses the weld spring, so that there is forward spring tension on the delta ring.

Then, simply insert the barrel into the upper receiver, making sure that the locator pin on the barrel extension makes its way into the notch on the top of the receiver. It should be a loose fit. If not, heat the receiver threads with a propane hand torch for about ten seconds and then it should slide right on.

Apply anti-seize in a liberal amount (liberal as in copious, not as in political) to the receiver threads and hand tighten the delta ring and nut to the receiver.

(Clockwise starting upper left) 1. Completing the delta ring assembly is much easier with a snap ring pliers. Use plenty of anti-seize to ensure the threads do not get galled and installation is smooth. 2. This nut is now “oomph” tight, at 30 foot pounds. It now just needs to be tightened until the next nut “scallop” is aligned with the gas tube hole in the upper receiver. 3. A firing pin makes a handy gauge for aligning the holes through the delta ring, spring and snap ring, nut, and receiver
(Clockwise starting upper left) 1. Completing the delta ring assembly is much easier with a snap ring pliers. Use plenty of anti-seize to ensure the threads do not get galled and installation is smooth. 2. This nut is now “oomph” tight, at 30 foot pounds. It now just needs to be tightened until the next nut “scallop” is aligned with the gas tube hole in the upper receiver. 3. A firing pin makes a handy gauge for aligning the holes through the delta ring, spring and snap ring, nut, and receiver

Taketh up thy AR action wrench and matcheth thy wrench’s scallops to those of thy barrel nut. You will have to push the delta ring back in order to insert the wrench’s teeth fully into the nut’s teeth. Tighten. Use a torque wrench (if you have one) with your action wrench and tighten to about 30 foot pounds.

If you haven’t a torque wrench, give it a small “oomph.” Loosen and tighten again; then go further the necessary amount to align the next hole in the nut serration to the hole going through the upper receiver. It may be a little, it may be a lot. Generally, once it’s oomph tight, you can still go almost a full hole segment further if you have to. I should point out that 30 foot pounds is a lot lighter than you think. It’s effectively a minimum spec anyway.

GAS TUBE

This is the trickiest part of the assembly of the upper. The end with the little knobby is the back end that goes into the receiver, and the end with the holes goes into the front sight gas block. With the upper in your vise, insert the back end through the barrel nut and into the upper receiver.

Adding the flash suppressor is simple. Place the crush washer with the wide end forward on the barrel threads and screw the device on. Use the large notch on the AR action wrench (DPMS model shown) to tighten. You have about one revolution worth in that crush washer, so don’t screw up.
Adding the flash suppressor is simple. Place the crush washer with the wide end forward on the barrel threads and screw the device on. Use the large notch on the AR action wrench (DPMS model shown) to tighten. You have about one revolution worth in that crush washer, so don’t screw up.

You will have to rotate the tube so that the bend in it allows the front end to clear the front sight, though you may still have to flex it just a bit to do so (a small amount is okay). It should slide right in, and if it doesn’t, then take it back out and ensure that you can see all the way through the delta ring, weld spring, nut, and snap ring. All should be aligned so that the tube will pass through into the upper receiver.

HANDGUARD

Now all you do is install the two-piece handguard. Include your wife in the project by having her insert the handguard halves while you are pulling the delta ring back. It is a stout spring. Install the top half first (they are identical) making sure you have the front ears properly inserted into the front retaining ring, just behind the front sight tower, and around the gas tube.

Snap in the rear end, and then do the same for the bottom half. Push the delta ring forward to fully seat it on the handguard. You will probably feel a little play in the handguard, but very little, and this is correct. If you want to feel more manly, rejecting your wife’s assistance, get a handguard removal tool from Brownells.

CHARGING HANDLE, BOLT, AND CARRIER

The charging handle, if not assembled already, involves simply putting the spring in the hole in the left side of the “T”, inserting the latch and stuffing the little roll pin in to retain it. Starting the pin before inserting the spring and latch, and retaining the latch with a punch will make things easy. Just drive the pin in and the punch will fall out.

The firing pin should move freely within the bolt bore and in the pin hole in the cam. Ensure that it does so prior to assembling the bolt/carrier assembly. Push the bolt into the carrier with the extractor on the right side.

The cam pin should then be inserted through the carrier and into the bolt and rotated ninety degrees so that the short sides of the pin’s top are pointed to the sides of the carrier. The firing pin then goes down the middle of the assembly from the rear and is retained by the little cotter style pin, which is inserted into the large chamfered hole on the left side of the carrier. Test the fit of the bolt by pulling it all the way forward and standing the assembly upright on the bolt face. It should not collapse.

Use a punch to align the hole in the gas tube with the hole in the gas block. Then tap in the roll pin to retain the tube.
Use a punch to align the hole in the gas tube with the hole in the gas block. Then tap in the roll pin to retain the tube.

If it does, and a new one should not, the gas rings should be replaced. It should also not require more than light force to move it. Too much friction, and difficulty moving, will prevent proper cycling and may be indicative of poorly manufactured parts. I know that’s subjective, but there is a feel to it, and in this regard, with new parts, you are very unlikely to encounter a problem.

The firing pin should move freely without restraint. Hold the assembly with the bolt pointing straight up, and flick the back of the firing pin.

If it doesn’t bounce up and down freely, then you probably have a problem with the bolt’s cam pin hole/cam pin interface, meaning you will likely need a different bolt as the hole is not properly sized or crimped. The firing pin should also only protrude through the bolt face when the bolt is entirely pushed into the carrier.

CONCLUSION

That’s the upper assembly. We’ll finish next month with the construction of the lower receiver. This was the basic assembly of the run-of-the-mill rifle. Of course, the deer rifle was significantly different. Since that goes onto a more upperclassmen type of assembly, I won’t go into great detail.

That upper was a JP Enterprises CTR-02 upper that I received and promptly took apart to have another feature from another company added. We’ll discuss that in our next excursion.

Click here to read Part I


custom-ar

Gun Digest Guide to Customizing Your AR-15

Whether you’re in the brainstorming phase of planning the future of your AR-15 and what it will become, or you’re already applying the finishing touches to your custom AR-15 creation, Gun Digest Guide to Customizing Your AR-15 by Kevin Muramatsu will help you wade through and understand the wide variety of available options for almost every imaginable variation. Though the array of AR accessories and customization options seems to constantly grow, turn to this book for an examination of the customization landscape and helpful recommendations for which options would work best for the growing population of AR owners.

Build an AR from Scratch – Part I

The C3 Defense lowers, surrounded by some of the small parts that go into them. Note the enhanced model on top with the integral trigger guard. These are excellent, excellent receivers.
The C3 Defense lowers, surrounded by some of the small parts that go into them. Note the enhanced model on top with the integral trigger guard. These are excellent, excellent receivers.

The gun-loving American is fortunate to live in these times. Even through the constant efforts of the statists, in the open or darkly concealed, we have at our fingertips the greatest assortment of firearms, and the greatest ability to possess them (Okay, not including early America), of any people that have ever lived. Also as Americans, we are innately susceptible to the “Flavor of the Month” complex. We love the newer and hopefully better.

Our market economy allows any itch to be scratched. If someone wants to hang some thing on his rifle, someone else will produce that thing to be hanged, and another the method for the hanging. Higher tech materials and production methodology multiply the effects even further. In practice, this makes an almost limitless selection of goodies available to the modern American gun owner.

This brings us to the subject of this particular excursion into gun goodness. The current flavor of the month (decade, really) is the AR-15. While this rifle has been discussed and touched upon in this column in more than one installment, the actual elaboration of the beginning to end construction of such a device has not been explored, and indeed is difficult to do, as there are so many steps to go through.

The proper alignment of the cover spring, with the short leg touching the port, and the long leg lying in a groove on the inside surface of the cover. It’s important that this step is completed before attempting to install the barrel.
The proper alignment of the cover spring, with the short leg touching the port, and the long leg lying in a groove on the inside surface of the cover. It’s important that this step is completed before attempting to install the barrel.

Don’t confuse multiple steps with complexity, however, as this is easily the simplest repeating firearm to assemble, requiring very few specialty tools. The average homeowner or tinkerer has most of the tools required.

Post the recent elections, the sales of ARs and similar themed firearms skyrocketed. Indeed, beyond the purchase of complete rifles, many thousands of stripped lower receivers were obtained, often with customers buying several “for a rainy day.” Most were shoved in a safe, but others were destined to be built to conform to the owners’ mental architectural designs. Manufacturers rushed to fill the demand for these lowers, delaying production of other components in order to feed the buying frenzy.

So what do we do with those stripped lowers? This author decided to explore a pattern of extremes. Building an inexpensive (not “cheap,” however), affordable carbine, and building an expensive (“expensive”) deer rifle should sufficiently illustrate the wide range of possible outcomes.

WHAT RECEIVERS ARE THOSE?

I chose to order my stripped lowers from a new company on the scene, C3 Defense (www.c3defenseinc.com, 678-363-5899). When initially ordered, C3 offered only upper and lower receivers, but they have now expanded into full rifle production, concentrating on the personal defense and law enforcement markets. C3 Defense is one of the expanding numbers of manufacturers that are machining receivers from billets rather than forgings (the normal run of the mill Mil-spec method). These types of receivers are identified by a more linear, “slab sided” appearance, one characterized by straight lines rather than curves.

They do tend to be a bit heavier, but cosmetically and functionally have properties that forgings do not.

Both C3 lowers show these trends. Thicker sidewalls allow a more aggressive magazine well bevel, more structural reinforcing around the buttstock attachment area (weak point), mag well, bolt catch, mag catch, and trigger guard, a raised gripping surface on the front of the mag well, and a great looking appearance. The enhanced model also features a machined-in expanded trigger guard, large enough for thick-gloved fingers.

Both sport a helicoil in the pistol grip screw hole (these threads are easily cross threaded, but not now), and a nylon tipped screw to place tension on the rear lug of the upper receiver to keep the rattle down, and enhance accuracy. Made of 7075 aluminum, the anodizing was flawless and completely even. This doesn’t happen much. Most AR receivers have some little color or finish flaws, and one major manufacturer, a while back, had at least one production run that was actually purple.

Most impressive was the mag well. Some manufacturers finish cut the mag well by wire EDM, but most use a broach to form the corners of the well. Broaching has a tendency to bow out the sides a bit, leaving a mag well that is not perfectly “square” with the outer wall. The result is a tight mag well that pinches magazines from the sides. Wire cutting them makes a perfect cut, but is more expensive. These lowers were broach cut and showed no bowing, and from a gunsmith and armorer’s standpoint, this showed top quality control and attention to detail. Very pleasing to see.

The rifle parts kit came from Del-Ton (www.del-ton.com, 910-645-2172), a known source that has a reputation for very competitively priced, yet well-made products, and a very customer friendly customer service. They have a variety of basic choices, all of which can be heavily customized at your whim with easy to use, drop down menus. The kit that was ordered was a 16” heavy barrel carbine flattop kit. Why that one? It was available, that’s why.

The flared mag well is obvious here. Also note the helicoil in the pistol grip screw hole and the tension screw hole just aft of that. These are all cool, useful features not commonly found on a standard forged lower.
The flared mag well is obvious here. Also note the helicoil in the pistol grip screw hole and the tension screw hole just aft of that. These are all cool, useful features not commonly found on a standard forged lower.

Everybody wants one of those silly looking M4 barrel kits. I didn’t care. I just wanted a kit. It includes everything needed to turn a stripped lower into a fully functioning rifle. This was used to build on the standard lower, the process of which is soon to be relayed. The enhanced lower will begin receiving next month a variety of my favorite parts from my favorite manufacturers, to produce the ultimate AR deer rifle.

I should point out that to illustrate in this article, Del-ton kindly sent me the kit in parts, but normally they sell rifle kits with the upper half already assembled. The following processes should be representative of any basic part or kit builds that the reader would likely attempt.

SO LET’S GET STARTED

You need the following tools:

•Bench vise with hard padded jaw covers
•AR-15 action wrench (pick one, they all work and you must have one)
•Carbine stock wrench (absolutely necessary, but cheap, like ten bucks cheap)
•Upper receiver vise block (not completely necessary, but very useful)
•Needle nose pliers
•Anti-seize
•Brownells or Wheeler screwdriver set (I have both and love them both)
•Punch set
•Roll pin punch set
•Roll pin starter punches are recommended as well
•Small hammer
•Fingers with a moderate amount of dexterity
•GO, NOGO, and Field headspace gauges (you can pay your gunsmith a small fee to test headspace, but they are nice to have)
•It also doesn’t hurt to have a few spares of the really small springs and detents. I won’t bother to tell which ones. You’ll figure it out.

A stripped upper needs these parts, the completely useless forward assist assembly with spring and pin, and ejection port cover with spring, pin, and clip. The handy white T-lettering helps you to remember where you mounted the scope, after you took it off to clean the rifle.
A stripped upper needs these parts, the completely useless forward assist assembly with spring and pin, and ejection port cover with spring, pin, and clip. The handy white T-lettering helps you to remember where you mounted the scope, after you took it off to clean the rifle.

We’ll begin with assembling the stripped upper receiver. The first thing to do is to add the completely useless forward assist. This is used to fill the large hole on the right side of the upper that houses the completely useless forward assist, preventing lots of hot gases from coming out of that hole that should house the completely useless forward assist (like the arguments supporting evolution, this is called a tautology). It is retained by a simple roll pin. Put it in, then function test by inserting the bolt carrier in the upper and pushing the big button. The carrier should move slightly forward, thus displaying that even a completely useless device can still justify its own existence.

Next: the ejection port dust cover. Put the little E-clip in the slot on the cover pin first. After you drop it, pick it up and try again. Then insert the other end of the pin about one fifth of the way through the front loop on the receiver. Take the cover itself and put it in place and push the pin until it comes halfway through the gap in the middle. With the cover in the open position, place the spiral spring on the pin so that the long arm is on the inside of the open cover.

Then twist the short arm of the spring so that it will bear against the bottom edge of the ejection port, while simultaneously pushing the pin all the way through the spring, cover, and rear loop. From the installer’s perspective, the long leg will be pointing down, on top of the cover, and the short leg will be pointing up into the ejection port. Test it by closing the cover and inserting the bolt carrier. The carrier should cause the cover to spring open.

If the port won’t stay closed on its own, check that you put it on with the little springy detent on the top positioned to the inside when the cover is closed. If you put the thing on backwards, you deserve ridicule. Don’t show your face in public for at least 14 hours.

That’s all we have room for this month. We’ll continue the detailed examination of this build as it progresses next month. Till then, go out and buy another lower or two. The buying spike has all but flattened, and the manufacturers really need to keep selling stuff. Plus then, when the ban legislations actually start showing life, and you know they will eventually (probably in December of 2010 or 2012), you will already have something to build on. Or sell.

This article appeared in the November 23, 2009 issue of Gun Digest the Magazine.


custom-ar

Gun Digest Guide to Customizing Your AR-15

Whether you’re in the brainstorming phase of planning the future of your AR-15 and what it will become, or you’re already applying the finishing touches to your custom AR-15 creation, Gun Digest Guide to Customizing Your AR-15 by Kevin Muramatsu will help you wade through and understand the wide variety of available options for almost every imaginable variation. Though the array of AR accessories and customization options seems to constantly grow, turn to this book for an examination of the customization landscape and helpful recommendations for which options would work best for the growing population of AR owners.

What Shall I Do With That Old Mauser? Part 2

The tools the author used to re-barrel a mauser to 45 ACP.
The tools the author used for barreling the .45.  A finishing chamber reamer, Go and No Go headspace gauges, floating reamer holder, the rifle’s bolt, Kuhnhausen shop manual on the Mauser rifles, the prepared, painted receiver, and the indispensable depth micrometer.

With a little imagination and a lot of skill, you can create a .45 ACP Mauser rifle. It doesn't matter why. This project is just plain fun.

Last issue we played around with modifying an old 8mm Mauser into a .45 ACP.  It was just one of the mostly meaningless jaunts into guncrafting goodness that turned out to be a fun, creative challenge.  I’ve already completed the magazine modifications and the construction of a new magazine well to make use of .45 ACP cartridges.  The remaining tasks to be done are to fit a barrel to the gun and figure out how to shorten the bolt throw, without of course, cutting out a chunk of receiver (and bolt) and welding it back together.

Getting Started

The first thing to do was the most difficult, or at least the most time-consuming chore. Initially I determined just how far I wanted the bolt to cycle, and where the ejector should be located.  The receiver had a “thumb hole” in the left side to accommodate thumb clearance when using a stripper clip to load the gun.  Basically it was a scoop out of the left side of the receiver just above the bolt rail way.

Cutting the taper is easy with the right compound rest.
Cutting a taper using the compound rest is pretty easy, as long as, like the author, you can temporarily control your caffeine shakes.  Using 180 sandpaper to smooth out the contour after the cutting is done blends it all together seamlessly.

I decided to move the ejector up to just in front of this scoop and to make use of that scoop to place the new bolt stop.  In order to accomplish this job, I milled out from a piece of half-inch square steel bar stock a new ejector housing that spanned from the housing screw hole and arms on the left rear of the receiver (where the original ejector housing and bolt stop had been) all the way to an inch or so forward of the scoop.  I then had to make a slot just in front of the scoop so the ejector could project into the bolt way from the ejector housing.

Forming the ejector housing was pretty easy, making measurements with a caliper of the bends, turns, and corners of the receiver, and then milling the block to fit.  The original hole where the bolt stop projected into the receiver and the original ejector slot were used as guides to align the new housing along the receiver.  A small flanged projection fitted in this area to align the housing.  In the “scoop” area I simply left a whole big block of material that pretty much made a false wall in the scoop.  I drilled and tapped a hole near the front of this blockish mass and inserted a quarter-inch long 4-40 socket head screw.

Then I ground a slight bevel on the rear of the tightened screw.  When pushing the bolt forward, the left side bolt lug contacts that small bevel, pushing the housing out slightly and allowing the bolt to pass, while pulling the bolt back forces the lug to impact the unbeveled front of the screw, stopping it in its tracks.  To finish this piece off, I cut an angle on the outside front of the housing and then milled a few flutes into the top, bottom, and left sides of the housing.  I then painted the housing with the same black Aluma-hyde II that covered the receiver.

How to Make it Go BIIING!

Now that the bolt stop had been created, I now had to make the ejector work.  I wanted to keep the original ejector and not have to fashion a new one from scratch.  I milled into the front end of the housing a slot to fit the ejector and drilled a hole for a roll pin for the ejector to rotate upon.  Then I slowly modified the ejector to project out sufficiently to insert itself in front of the bolt when the bolt was fully open.  I made two small cuts in the outside of the ejector, creating a spring guide of sorts for a small spring (just happened to be the bolt stop detent spring from an AR-15).

This spring pushes the ejector against the bolt, forcing the front of the ejector into the ejector slot on the left side of the bolt face as the bolt is pulled back, making contact with the left rear face of the cartridge case head.  Of course a relief hole was drilled in the ejector housing to accommodate the spring.  I effectively did all this by eye in little increments, and it was pretty time-consuming.  In the future, if I do this thing again, I will spec out some measurements based on this housing, but this time I was shooting as I went along.  Fortunately, the housing slot aligned perfectly with the slot cut into the receiver.  This is probably because I did precisely calculate that particular task, and it was rock steady because of the “guides” previously mentioned. See! I’m not a complete “wing it” gunsmith.

Frustration and Correction

The completed ejector block.
The completed ejector block.

I should also make note of the ejector housing ears on the left rear of the receiver.  I thinned them out by a few thousands by polishing to reduce the friction back there.  My first thought for a tension spring was to place a small loop spring in between the ears.  That didn’t work.  This tension is, of course, very important as it serves to keep the entire housing flush against the left side of the receiver, and it has to be stronger than the ejector spring that was pushing against the bolt.  This one really stymied me; I had no room or leverage to work with in the back, and there didn’t appear to be any other way to make this work.

Then, with a 100-watt light bulb pulsing above my head, I cut off a piece of the original flat magazine spring, still slightly curved, and about one inch long.  I drilled a hole near one end and used the bolt stop screw to hold it in place on the inner false receiver wall of the ejector housing.  This spring extended back to make contact with the inside wall of the receiver, back where the original ejector entered the receiver.  It was thin enough to not interfere with the bolt, but had enough tension to just barely keep the ejector housing pressed tight to the receiver, and just enough give to allow the housing to be pulled out enough to allow the bolt lug to pass by the stop screw so that the bolt could be removed from the rifle.  This detracted a tiny bit from the clean lines of the gun, as when the bolt was pulled out there appears this ugly foreign-looking flat spring thing.  But it works and that was enough for me.

Last But Not Least

Barreling the gun was vanilla.  I first contoured the barrel down to about what the original barrel’s diameter measured, and made it 16 ¼ inches long.  It’s truly amazing how much lighter a barrel blank becomes after you cut a third off the end and turn it down a bit.  I wanted to make sure that the outside diameter and bore were concentric the whole way so I trued the muzzle end and reversed it, put that end in the lathe chuck and stabilized the barrel with a live center and steady rests on the other end before the final contouring cut. I can say with pretty certain authority that this barrel, unlike ANY you get on a factory gun, is truly concentric.

The ejector block from the left side. The author was quite proud of the way this assembly turned out, as it looks really darn cool.
The ejector block from the left side.  The author was quite proud of the way this assembly turned out, as it looks really darn cool.

I put a taper in front of the chamber that roughly matched the factory barrel, though not exactly, as the original 8mm barrel was stepped.  On the muzzle I installed a completely unnecessary muzzle break.  I say unnecessary, as a .45 produces little gas to redirect, and the recoil from a .45 carbine is best described as a gentle push.  But it looked cool, so I did it anyway.  I also permanently attached this brake since there would be no reason to remove it in the future.  I threaded it on, timed it to align properly, drilled a hole through it, pinned it, and took it to my gunsmith buddy Mark to weld the pin in the hole (I didn’t have welding equipment readily available, and besides, he’s better at welding than yours truly).

I was also able to cut a superb chamber with minimum headspace thanks to the virgin reamer I purchased from Dave Manson Precision Reamers.  New, quality reamers like this one cut as if the steel was actually butter, as long as you don’t reverse the cut and dull the tool.  Or allow the reamer to get clogged with chips.  Or not use sufficient cutting fluid.  Or feed the reamer too fast.  Or not use a floating reamer holder.

Or think you’re really slick and ream the chamber on high speed.  For the record, I’ve never done any of those things. Ever. I’ve also found that cutting the chamber to just fit the Go gauge before final fitting on the receiver, then tightening the barrel onto the receiver of a Mauser, still leaves plenty of headspace room when complete, pretty much eliminating the need to calculate any crush factor inherent in the chambering process, and removing the need to use an extended shank reamer to finish the chamber after tightening the barrel down.  The No Go gauge still doesn’t even come close to fitting.  I also acquired the Go gauge from Manson, paying for the mistake I made by loaning my previous gauge to another gunsmith some time ago.  Never loan a gunsmith ANYTHING.  It will disappear into his bottomless gunsmith packrat box.

The final duties to perform were to put the gun in the stock, get some kind of sighting system on it, and test it.  I simply added a small section of Picatinny rail to the top of the barrel shank and topped it with a JPoint Microelectronic sight.  This red dot is rather small, rather light, and rather expensive; so I borrowed it.  But it was perfect for the gun and looked pretty neat perched just in front of the receiver.  I suppose I’ll have to buy one of those now too.  Concluding the project, I nailed the barrel with Aluma-hyde so that the entire barreled action was a nice matte black, re-inletted the stock to fit the new barrel and ejector housing, and then put off until later the minor contouring that was necessary to blend the exterior lines.  I just wanted to shoot it.

Okay, this was really cool.  I’ve mentioned before that I’m not a good shot.  But I did put a five-shot group at 25 yards into a single ¾-inch hole, no lie.  The group opened up to three inches at 50 yards.  I blame the 8 minute-of-angle dot in the JPoint.  The dot simply covered the entire target and was thus difficult to center on the bull’s-eye at that range.

Guess that extra concentricity work paid off.

You Know You Succeeded When …

I then showed this project off to a couple friends and then my father and uncle.  You know you’ve done something right when a guy gives you a puzzled “what the heck is that?” look, and shoots the gun.  Then he turns around slowly with a really stupid grin on his face, with a little bit of drool hanging off the corner of his ‘stache, and then proceeds to turn back around and empty your magazine.  My favorite quote was “Hey! You could load this thing up with Cor-Bons and deer hunt with it!”

Well, lookitthat! I’ve got a practical use for this thing after all!

Read Part 1 of Project 45 ACP Mauser

What Shall I Do With That Old Mauser? Part 1

 
Yes, this project requires the use of a mill, but it’s still a really cool project. And remember some of the coolest projects aren’t always the most useful, but they are still fun to work.
Yes, this project requires the use of a mill, but it’s still a really cool project. And remember some of the coolest projects aren’t always the most useful, but they are still fun to work.

Muramatsu converts a Mauser to .45 ACP in this two-part series. Why, you ask? The best reason of all: It's fun.

Some of the coolest things in the gun world are those with no serious application.  Or perhaps those applications are in the eye of the beholder.  One of the neatest things I have seen is a conversion for an old favorite that is little more than just plain fun.  But that’s good enough for me.  I figured if I needed a “sporting” use for it, I could take it swamp buck hunting with some XTPs.

All You Really Need is Raw Material

The right side of the assembly showing the strangely familiar button.
The right side of the assembly showing the strangely familiar button.

It used to be, in the olden days of gunsmithing, that gunsmiths were customizing and sporterizing a myriad of used (sometimes very) military rifle.  Carcanos, Arisakas, Enfields, and Springfields were cut down, welded, gutted, rechambered and rebarreled, sighted and scoped.  However, the most customized rifles were probably the Mausers.  Okay, yes the Springfields and Arisakas were derived from Mausers, derived being the key word.  Mausers didn’t have those stupid magazine cutoffs or the ridiculously difficult safeties.

Mausers came back from Europe by the thousands.  Unfortunately, the 7.92x57mm (8mm Mauser) ammunition to shoot through them was not as plentiful, so many, many of these Mausers were rebarreled or rechambered to shoot something more easily appropriated:  .30-06 Springfield, 8mm-06, .270 Winchester come to mind.  Interestingly enough, many years later when your humble author was in gunsmithing school, he came upon one of his fellow students turning a Mauser into a .45 ACP with a kit that he purchased online.  That kit is no longer available, but I figured it wouldn’t be all that difficult to replicate one on my own from scratch.

I want to point out that unlike most of the stuff done in this column, to do this project involved heavy use of a lathe and mill.  I also removed the original magazine floor plate, spring, and follower and tossed these and the retaining button into the gunsmith packrat box.

How Am I Going to Do This?

First off was the easiest part of the whole procedure.  The case head diameter of a .45 ACP is only slightly larger than an 8mm Mauser.  Using a Dremel tool with a small grinding stone, I ground off a touch from the extractor claw, just enough so that a .45 ACP case would stay held in its grasp.

The second task was to brainstorm how to feed the ammo.  Most gun owners will readily acknowledge that other than the case head, .45 ACP and 8mm Mauser aren’t even close to being similar.  Like in the old kit, I decided to use 1911 magazines as a feeding device because of availability and compactness. I needed to construct a magazine well block that would fit into the original magazine box on the gun yet have a magazine well of its own inside it to accept the 1911 mags.

I needed to figure out a mag catch too.  Well, what I had available was a big block of Delrin plastic.  I milled it out to roughly the right size for the magazine well dimensions but oversized by about 10 percent.  I then cut it in half.  Using a 9/16-inch ball-end mill I cut lengthwise the magazine channel (at a 14-degree angle to match the angle in the 1911 pistol), intending to use the rear half of the block to form the back of the mag well only.

Looking up into the mag well reveals the mag catch’s latch. The Delrin proved to be a very effective and smooth surface for the mag.
Looking up into the mag well reveals the mag catch’s latch. The Delrin proved to be a very effective and smooth surface for the mag.

This worked out pretty well and was an easy way to cut the channel. I was then able to carefully use a belt sander to precisely shape both sides together to match the channel, and tightly fit the block to the mag well. I then fastened this block to the mag well of the Mauser by drilling two 1/8-inch holes in both the front and rear of the mag well and pushing through four roll pins.  The block protrudes about ¾ of an inch below the bottom of the mag well, and thus the stock, but I thought that it looked too skinny and rough.  So I fastened two sheets of smooth plastic, one on each side, to the block using an epoxy.  After the epoxy had cured, I again touched up the whole assembly on a belt sander.

Now to make this feed properly, I had to make the magazine sit so that the feed lips were just below the closed bolt of the rifle, but high enough so that the bottom of the bolt face could catch the top of the first cartridge in the magazine. I had already decided to use an AR-15 magazine catch assembly, just to see if I could pull it off.  I simply machined the slot out of the left side of the block and drilled through to the right side for the post of the mag catch.  On the right side, using the drilled hole as a starter, I milled the ovoid hole for the button and then opened the hole up with a 1/4-inch drill until it came to within 3/32 of an inch of the slot in the left side.

The Derlin worked well for the magazine well because it was easy to work with and strong enough to do the job. Other parts were fabricated from scrap. Looks good, doesn’t it?
The Derlin worked well for the magazine well because it was easy to work with and strong enough to do the job. Other parts were fabricated from scrap. Looks good, doesn’t it?

This deeper wider hole was to accommodate the mag catch spring.  I had to shorten the spring by half to make it fit properly, as this whole assembly is about half the width of the AR-15’s mag well.  After assuring that this mag catch would function properly, I removed it and inserted the magazine to the proper depth.  Looking through the slot, I was able to mark on the magazine with a scribe where the mag catch slot was located.  I then removed the magazine and with the mill, machined a small slot at the scribed location.  Fancy that, it even worked.  Inserting the magazine into the new mag well should be smooth without too much wobble and some friction should be apparent from the magazine catch until the catch snaps into place in its slot.  I did find that the slot I cut was too wide, so I decided that I did indeed need a stop to keep the magazine from going all the way through the action when the bolt was open.

I dug out a hole in the front left “corner” of the mag well at the top, just deep enough to be level with the notch in that portion of the magazine.  This notch is intended to give clearance for the slide stop in the 1911 pistol, but in this case provided a satisfactory point to place a magazine stop.  I used a scrap piece of steel (in fact, a useless, used and worn AR-15 disconnector), ground down to the proper shape on the belt sander.  I used the original trigger pin hole as a screw hole with which to fasten it to the magazine block.  I duplicated the radius of the magazine front to allow it to protrude just slightly into the magazine well.  After drilling and tapping this hole into the block I screwed down the new mag stop and inserted the magazine to check the fit.  It stuck out a little too much.

Visible here are the four through pins that hold the block in the mag well. The block is also retained by epoxy. The slot for the magazine catch is also clearly visible, as is the slot’s protrusion into the mag well.
Visible here are the four through pins that hold the block in the mag well. The block is also retained by epoxy. The slot for the magazine catch is also clearly visible, as is the slot’s protrusion into the mag well.

So, using a Dremel tool with a grinding stone,  I shortened it just enough so that it would interfere with none of the cartridge dummies in the magazine.  With the magazine set in the well, there was a very small amount of “jiggle” play, which turned out to be insignificant.  The bolt perfectly stripped dummies off the magazine when pushed forward.  In fact, once the dummy cleared the feed lips of the mag, the follower literally popped the dummy right up underneath the extractor.  This was a pleasant surprise.  It was inordinately fun to fill up the magazine well with dummies and cycle them through the action to let them fall out the front of the action.  Sometimes it just feels good to do things right.

I then finished off the whole assembly with Matte Black Alumahyde II from Brownells.  This turned the appearance from warmed over junk to a halfway decent looking gun assembly.  Convenient too, since it is an aerosol and doesn’t require baking, which was good since a significant amount of the assembly was plastic.

So, What's Next?

So now that the magazine block was complete, and it even worked, I needed to move on to the next step.  I decided to leave the barreling until last.  One of the experiments I decided to conduct was to shorten the bolt throw and move the ejector forward so it was just behind the new magazine well.  And of course this little piece wouldn’t be complete without a completely unneeded muzzle break to help tame the mighty recoil.  We’ll detail all this and more in the next excursion into the world of gun goodness.

Click Here to Read Part 2 of Project 45 ACP Mauser

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