Colt AR15 Barrel Break In

[Jax970]

Trying to help a buddy out...

He has a Colt AR15 that needs to be broken in. He said the manual states to only use 5.56 ammo for the first 20 shots during the break in period. After that you can use .223. He knows a 5.56 rifle will shoot .223 and he knows not to shoot 5.56 from a .223 rifle. Does anyone know why Colt says to use 5.56 for the first 20 shots?

[Spiffy]

No idea on why Colt says that. 99.9% of responses I have seen to "barrel break in" is to just shoot it and shoot it and shoot it.

[Guest 70below]

Only a guess, but I'd say it has more to do with getting the bolt, carrier, buffer, and spring to cycle under full load of the higher pressure 5.56 loading.

[Guest TurboniumOxide]

Crap, you are supposed to break these things in? I just took it to the range and put 7 magazines through it with a mix of 556 and 223 from several different manufacturers. The barrel was smokin hot when I got done. Hows that for a break in? There wasn't a lot of copper in the barrel when I cleaned it, and the bore looks fantastic afterwards.

[Spiffy]

Crap, you are supposed to break these things in? I just took it to the range and put 7 magazines through it with a mix of 556 and 223 from several different manufacturers. The barrel was smokin hot when I got done. Hows that for a break in? There wasn't a lot of copper in the barrel when I cleaned it, and the bore looks fantastic afterwards.

Yeah you really messed up your gun............send it to me for proper disposal

[Guest donfromtexas]

So what exactly is a "break-in" for a barrel anyway?

I have shot brand new Berreta 9mm's, brand new AR's (M4), brand new M240's, brand new M2's, and brand new 120mm smooth bores without ever having been told that there was a break in period or requirement.....

I am just wondering because I have fired many brand new weapons without ever "breaking" them in and have never had any type of problem from any of them. They were all properly cleaned and maintained after firing.

Just wondering... any professionals out there with an idea?

[Spiffy]

Breaking In a barrel is mostly for benchrest shooters. Like shoot 5 round and clean shoot 5 more rounds and clean again. Repeat till you shoot 200 rounds.

[crashgordan]

stainless steel breakin is different then carbon steel w/ chromoly bore...

but agree w/ above.. mostly for bench shooters.

shoot it clean it, done.

[LA_357SIG]

Barrel Break-In

Take it for what it is worth.....

[Guest TurboniumOxide]

So, basically, clean your barrel before your first shoot. Put 200 rounds through it, and clean it again until all the fouling is gone. Good to go.

[Guest Glknknox]

Just shoot it.

Did that with my very first one, just a waste of time unless your doing the bench rest/tack driver thing.