According to the Bushmaster web site, you should keep cleaning to a minimum for the first "couple hundred rounds", stating that shooting the gun will polish/burnish the bore. Does this sound right ?

I'd tend to agree with the weapons manufacturer.

IIRC, I put like 500 rounds through my Bushy HBAR before cleaning it the first time.

I did run a patch with some CLP on it through the bore before shooting the gun though. Not a real "cleaning" just to dust out the bore, and make sure there were no metal shavings in there.

IF it is chromed lined just take it out and shoot it, many times

Holy shit, you're supposed to clean a chrome bore!?!?

I've got about 800 rounds through my Bushy pencil and I've only swabbed the barrel once.

I did run a patch with some CLP on it through the bore before shooting the gun though. Not a real "cleaning" just to dust out the bore, and make sure there were no metal shavings in there.

ALWAYS a good practice on a new firearm.  Follow that oily patch with a dry patch, you don't want excessive oil.

My breakin of new barrel.  Load a 30 rnd mag.  Shoot all 30 rnds as function test.  Drop empty, reload with another 30 rnds.  Shoot all 30 rnds.  Now it's broken in.

Thanks, guys! I have two AR's with chorme-lining and just shot the snot out of them when I first got them. I've got a couple more on the way and just didn't know if I should treat tham a little gentler as pups. But I see your points, I shot a one hole group off the bench last week with one of my 5 year olds, so I guess it didn't harm the bores one bit...

Chrome lined barrel break in:
Load up 3 Beta Mags
Bump fire each Beta Mag in succession as fast as possible.
Quench barrel in a bucket of ice water.
Repeat as necessary....


I'M KIDDING OF COURSE!  

Scott: do you have three betas I can borrow? I like your method the best so far...

Would cleaning between trips to the range (say... 100 rds per trip)  cause problems with the break in?  or just delay it a little....

I guess I'm asking... you wouldn actually "hurt" the barrel with a light cleaning during break-in?
(I'm not talking about a brush-scrubbing here either... just some hoppes #9 patches,  dry patches, followed by fp-10 and a dry patch.)

I've got about 350 rounds through my RRA chrome-lined midlength,  and I've cleaned it probably...  2 or 3 times.  

I notice that at first,  I was getting 2 groups at 100 yds... one dead center,  one about 3-inches away at 11:00, both very tight.

When I shot yesterday,  I got the same thing,  only the 11:00 group was only about an inch away.

On seeing the double-grouping, another shooter on the range suggested it might be a "break-in" thing.   Perhaps he was referring to a different component - not necessarily the barrel.  (the shooter?)