Hey all,  new guy here with a new Stag in route (M4, 16" 1/9 barrel).  This is my first AR to actually own but not first to fire (7 yrs in Army).  What kind of ammo should I run through it for a thourough barrel break-in? I'm thinking whatever shoots through it (surplus, Wolf, any non-corresive round), but I've never shot an AR in the break-in phase.  From what I've read, roughly 300 rounds should settle everthing down (comments/feedback welcome on this).  

I'm impressed with the amount of knowledge and insight found within the threads of this forum.  After trolling through here for a few weeks, this forum has provided a wealth of information, especially the info used in my decision of the Stag rifle.  Keep up the good work guys.

-Dbo

the most expensive ammo you can find.

I used winchester 5.56 which is q3131, it's a hotter load than any commercial .223.  I figured I'd use hot loads to break in all the parts real well, in hopes that I would be able to use weaker loads like wolf .223 later. So far, it's worked, Wolf will cycle just fine, but I'm not sure if it has to do with the Gun, or the way I broke it in. I say use hot stuff, I don't think it can hurt.

Okay, sounds like hot and/or expen$ive loads are the way to go; thanks for the input guys-

Shoot whatever you plan on shooting for BARREL break-in.  It's the cleaning process between firings coupled with the actual shooting that smoothes the fine tool marks.  If you have a chrome bore don't worry about it.

Breaking in the rifle, use the ammo that goes bang.  Their isn't any rifle "break-in" process.  It should function like it is supposed to from the get-go.  So, any ammo that cycles the bolt and exits the barrel will work fine.

Oh yeah, don't say you were trolling around.  Trolling is for assholes.  You were browsing, reading, lurking, etc.

I use the hotter stuff for break-in like your standard WWB from Wally World (I don't mean the barrel, I mean the initial smoothing of the moving parts) because the weaker stuff like Wolf might not be able to overcome the extra friction in the system in the first couple hundred rounds.

After that, Wolf is the name of the game

Haven't had any problems yet.

WIZZO

I bought a new Stag M-4 last fall.  After 40 rounds of WWB, I started hitting it with the Wolf with no problems.

Dbo,
    I will have to disagree with not breaking the barrel in, even one with a chrome bore. The chrome is about twice as hard as the rest of the barrel, but the bullet & the hot gasses will have some effect on the bore and the throat. I have a 16" Bushmaster fluted HBAR with a chrome bore that showed definate improvement over the break in period. It will group 0.9" @100yds. The 24" Bushy Varminter barrel, which does not have a chrome bore, has grouped 0.28" @100yds after the same labor intensive break in. 5-1s (clean after each round), 5-2s (clean after each 2 rounds), 5-3s, 5-4s, 5-5s. The only barrel I have that did not show a significant improvement during break in is a Krieger SS hand lapped barrel. It shot 0.38 from the get-go and required practically no break in. It is the easiest barrel I have ever owned to clean. You get what you pay for with a premium barrel.
    I have used Wolf and Winchester white box to break in different barrels. Both will work, but it is a whole lot easier to use the cleaner burning Winchester ammo IMHO.
    Get a good cleaning rod guide , use a good coated 1 pc. rod, always wipe the rod clean before each use, and clean the bore down to bare metal after each shot or group. Most barrels are ruined thru improper cleaning techniques. Shoot groups as you go using match ammo and see if you are making a difference.
                                                                  HTH,
                                                                  Carey

double-posted.