Sporting rifle magazines, actions, and triggers, like a good pair of boots, need to be broken in. The mag, action and trigger also all have moving parts. When broken in, these components will operate more fluidly and more consistently, than when they were new.
But did you know that your AR-15’s barrel, despite the fact that it is a non-reciprocating, non-moving gun part, also needs to be broken in?
Here’s what you need to know about the whole process. Grab some American Eagle .223 and some cleaning essentials, here’s your primer on AR-15 barrel break-in.
What’s the Point of Breaking in an AR-15 Barrel?
During manufacture, the process of cutting rifling in the AR-15 barrel is typically done through a procedure known as button rifling, although rifling can also be cut through the barrel (the traditional, old-school way) or hammer-forged, a relatively modern process.
Regardless of the method used to produce the rifling inside the bore, there will be machining or forging inconsistencies that leave small burrs, microserrations, and other micro-aberrations on the inside of the bore.
And, regardless of the fact that you can’t see them (because they’re inside the barrel) and that even if you could see the inside of the barrel, these minor inconsistencies are too small to see with the naked eye, they can impact accuracy.
This is the reason that a well-worn barrel that has had a few hundred rounds through it, and even maybe a little bit of copper fouling, will often produce tighter groups than a brand new barrel.
So, the long and short of it is this: the process of breaking in an AR-15 barrel is to mechanically lap it to polish away these imperfections, and you do this using a series of jacketed bullets along with meticulous, thorough cleaning.
The end-game here is that a rifle barrel that’s properly broken-in will be slightly more accurate than one that’s fresh from the factory. And if you’re competing with your rifle or shooting or hunting at long ranges, that sort of thing matters.
One more thing: a barrel will break in naturally with time and use. You do not actively need to break in your AR-15’s barrel. That will happen on its own. This short guide is just intended to show you how to fast-track that process.
How to Do It
There are two main things you will need to break-in your AR-15’s barrel. You will need some fully-jacketed ammo and a rifle cleaning kit. So get together your barrel brush and some American Eagle .223 and set aside some range time.
Start by thoroughly cleaning your rifle before you get to the range. You want to eliminate all oil and grease from the bore that might be left over from the factory. This will just combine with the copper and powder fouling from your ammo and create tar, making it harder to clean the barrel afterwards.
Visit the range and fire a single round through the barrel. Then clear the weapon, remove the magazine, and thoroughly clean the barrel. Clean it till all traces of oil, grease, powder and copper fouling have been removed, then allow it to dry.
Once dry, fire another single round through the barrel and repeat the process. Repeat this for 5 to 10 single rounds.
Once you’ve completed between 5 and 10 one-shot cycles, start 3-shot cycles, in which you fire three rounds downrange and then clean the barrel. Repeat the 3-shot firing and cleaning sequence 3 to 5 times.
Once you’ve completed your one-round and three-round sequences, fire 5 shots through the barrel and then clean it thoroughly, removing all traces of oil, grease, copper and powder fouling. Repeat this process 3 to 5 times.
By the end of this, you should have fired anywhere from 29 to 50 rounds downrange, and thoroughly cleaned your barrel anywhere between 9 and 20 times. Also by this point, the bullets you’ve sent through the barrel should have done a pretty decent job of lapping the bore, smoothing out any aberrations that would complicate accuracy.
By this point, your barrel will either be broken-in or well on its way to being broken in, and you can start the process of sighting in the rifle.
Here for Bulk American Eagle .223 Ammo?
As you might have noticed, you’ll need at least a full box of ammo to get the break-in process completed, and realistically more than that. We can help with that - get some American Eagle .223 here or shop our 5.56 and .223 bulk ammo collections to stock up your ammo cans.
And remember, there’s no need to use ultra-premium ammo for break in. You can use basic jacketed bullets for this job. Save the OTM ammo for long-range shooting and the ballistic tips and hollow points for hunting. They’re way too expensive to burn on barrel break-in anyway.