Another option, and one I like a lot, is to have the BCG and/or hammer (or the full trigger group) plated with either Robar’s NP3+ nickel/teflon coating or Fail Zero’s EXO nickel/boron coating. Both have extremely high lubricity and will greatly reduce the need for additional lubricant. NP3+ has the advantages of higher lubricity & corrosion resistance, while EXO has the advantage of being considerably harder and therefore much more durable. So take your pick.

Personally my ‘go to’ AR uses a Fail Zero upper receiver that’s been plated in their EXO coating & then finished in matte black teflon on the outside. (I don’t like the dull gray look of either NP3/NP3+ or EXO as an external finish, and EXO does have the advantage of being able to have another finish applied over top of it. NP3 & NP3+ are far too slick to hold another coating. EXO also has the advantage of extending the life of the upper receiver by essentially eliminating wear.) On the inside of my carbine the trigger group & charging handle have both been plated in EXO, and the bolt carrier group has been plated in NP3+. This is a kind of ‘best of both worlds’ approach that pretty much eliminates the need for additional lubricant all together. I keep a can of Rem Oil in my kit, but I have yet to actually need it even when firing hundreds of rounds of ammo in a single day, even the extra dirty Russian steel cased stuff! The carbine just keeps chugging along without any problems. The other advantage is that fouling doesn’t stick to either NP3/NP3+ or EXO. This makes cleaning a breeze! Just wipe everything down with a dry paper towel and you’re pretty much done other than the bore. Honestly, this is the biggest reason I chose NP3+ & EXO plated parts when build this carbine; I’m lazy & don’t like scraping carbon.

On my other AR’s, which are not NP3+ & EXO plated, I generally use a good gun grease on the rails & underside of the BCG as well as a bit on the bolt’s locking lugs. Other than that I keep the aforementioned can of Rem Oil in my kit and give the BCG & the inside of the upper a good squirt every couple hundred rounds or so. AR’s generally like to run wet! That’s an important thing to remember if you want your gun to run reliably. In foul weather conditions, especially with blowing sand & dirt, it is also very helpful to keep the ejection port cover closed & a magazine in place to keep as much debris out of the gun as possible! AR’s have gotten a reputation as being somewhat unreliable, but, in my experience, as long as you keep the weapon properly lubed it will run reliably a very long time!