Massad Ayoob: The Dangers of Over-Penetrating Bullets

A look at over-penetrating bullets

Even the U.S. military is looking at switching from ball ammo to expanding bullets. This is Federal’s “Limited Penetration FMJ,” which uses Expanding Full Metal Jacket technology developed by Tom Burczynski to deliver a more effective wound channel in ballistic wax by Ballistic Technologies’ Bullet Test Tube and causing bullet to expand to 50-caliber or better.

Deconstructing Shootthrough Fatalities

Why would officers hit more of their own brethren than “civilian” bystanders in this fashion? For the simple reason that while victims and potential innocent bystanders tend to flee danger scenes, the cops are conditioned to “ride to the sound of the guns.”

In a close-quarters situation where a violent criminal is attempting to harm or even murder another officer, cops try to grab him or stop him or even maneuver into a position from which to shoot him.

All these actions can put them in the line of fire of brother officers.

Ball ammo is for practice

Ball ammo, like the excellent American Eagle at left, should be used strictly for practice in author’s opinion. The 147-grain JHP Subsonic as pioneered by Winchester (right) was better, but still erratic and unpredictable in its performance. Today, there are much better ammo choices than either of these antique rounds for “street” use.

Tunnel vision occurs in a majority of life-threatening encounters. This is the perceptual phenomenon of being able to see only the threat and being unable to cognitively recognize other people or objects that might be in the line of fire.

Moreover, the body of the offender may simply block the shooter’s view of the brother officer who is trying to apprehend or restrain the attacker from behind. In these situations, a “shootthrough” is highly likely to kill or cripple one of the Good Guys and Gals.

What does this have to do with private citizens’ use of CCW handguns? Only this: Where the cops jump in to protect their brother and sister officers, brave citizens may step in to protect their actual brothers and sisters, husbands and wives, sons and daughters, or fathers and mothers. Now it is your loved ones who are behind the offender – unseen by you – when you discharge your CCW weapon.

Those 115-grain jacketed ball 9mm rounds will pierce more than two feet of muscle tissue-simulating ballistic gelatin. So will 230-grain full metal jacket 45 hardball.

By contrast, the depth of the average adult male thorax is probably no more than 10 inches, from front of chest to back. Nor is it solid muscle: the
spongy tissue and large air volume of the human lung offer little resistance to a bullet.

A Real-World Example

Many years ago in Los Angeles, an Aryan Brotherhood thug took several people hostage in an office. He demanded an escape vehicle and threatened to start
shooting hostages if he didn’t get one.

A vehicle was provided, and he got into the car with the victims. At this point, the LAPD SWAT team launched smoke, and two members of the team whom I happened to know moved forward through the gray cloud, their issue Colt 45 automatics up and ready.

When the perpetrator reached for his pistol, the cops opened fire, using department-issue 230-grain hardball. They fired four shots between them, and killed the offender before he could launch a single bullet of his own.

Autopsy showed any of the four hits would have been quickly fatal. However, only one of those bullets stayed in the offender’s body. One of the three exiting slugs struck one of the hostages. Fortunately, the wound was not
in a life-threatening location.

LAPD quickly switched to hollowpoints, which is what they use today. Lesson learned.

mas-kit***UPDATE: Mas Collection Now 50% OFF!***

Gun Digest Book of Concealed Carry by Massad AyoobRead More from Massad Ayoob

This article was excerpted from Massad Ayoob’s book, The Gun Digest Guide to Concealed Carry. If you found this information about over-penetrating bullets valuable, continue reading by clicking here to order the book.




2 thoughts on “Massad Ayoob: The Dangers of Over-Penetrating Bullets

  1. wfluit

    Not only is hardball an excessive penetrator, its also a poor stopper. I’ve never been impressed by FMJ performance on the scenes I’ve investigated, even the fantastical .45 ACP “FMJ manstopper.”

    There’s been a fascination in recent years with bullets penetrating an auto’s front windshield. I don’t have the stats but I believe very few police shootings involve shooting thru the front windshield. Civilians IMO are even less likely to be in situations where they have to stop a BG thru the windshield.

    I’ll take a fast moving and fast expanding bullet. When I was still on-duty I would have gladly traded the Glock .40 for a Smith 66 .357 mag with 125 HPs.

  2. SmithKoWitz

    Thanks for reprinting this piece. There are still a lot of people out there who think a lot of these newer HP’s and especially Flextip rounds are insufficient. When I read about these bullets, they talk about 12 inches or better of penetration in gelatin. Yet here M.A. says that 10 inches is the average human front to back. Technically, you don’t need a bullet that penetrates more than 10 inches, on average you should be able to reach a vital organ in about 5 inches and 10 inches even in much larger subjects. As in hunting of animals, the same would hold true in self-defense; shot placement is the key. Now, for self defense against a wild pig, bear or mean goat, you might want something with a little more penetration; I’m guessing about 15 to 18 inches, but it would depend on the angle you were to the creature when shooting. The same would hold true with a human subject; a side shot could penetrate 12 to 14 inches without exiting most adult people, but 10 inches would still be sufficient if placed reasonably well. You could argue if an arm was in the way, and the clothes they are wearing, especially if winter. I suppose the answer then is: two mags, one with heavier penetration ammo than the other by about 3 to 6 inches. And you can stop and determine which one to load while the perp shoots at you . . . . nah, I’ll go with the safer ammo; I’ll stick with my Flextips in 45colt or acp and 357 or 40, depending on which weapon I am packing. For the big creatures, the 460 S&W mag.