Hey all, I have a problem that's really pissing me off now.  I bought a Stag complete barreled upper with a arms 40 on it from Bravo Co.  I went to the range last week and had to crank my sites way over to the right and still shoots left about 6-7 inches.  I loosen the barrel nut and re index the barrel.  Take it out to the range again and still shoots left with the sites all the way to the right.  Could there be a problem with the barrel?  Also, just looked at the target I brought back and the holes are oval, not round.  What's that...need help or should I just send it back to Bravo Co.

Thanks,

SFC

You are at least the third person who has posted that problem with the exact same NIB upper. I haven't heard the resolution yet.

Send it back. They will take care of you.

Got an email back from Bravo Co, said to give Stag a call.  I hate being without a weapon.  I talked with a number of NCO's from my unit and they said the crown was probably screwed up on the new barell.  That accounts for the keyhole affect at 25 yards and my ARMS 40  cants to the left a little when tightened down that's probably throwing me off to the left on top of the bad crown.

Quoted: Got an email back from Bravo Co, said to give Stag a call.  I hate being without a weapon.  I talked with a number of NCO's from my unit and they said the crown was probably screwed up on the new barell.  That accounts for the keyhole affect at 25 yards and my ARMS 40  cants to the left a little when tightened down that's probably throwing me off to the left on top of the bad crown.

I don't know about a nicked crown causing keyholing, but I have heard quite a few problems with the ARMS being canted/twisted requiring significant windage adjustment for zeroing.

Can you try a DCH or standard iron sights, or perhaps a scope?

Any resolution? I think you are not the only one with this problem.

a fellow NCO in my unit came back from the Colt Armors Course and said the crown was most likely the problem, maybe bent.  An F'd up crown will do what I told him and talked about the oval holes in my target and the keyholing affect.  I also took the ARMS 40 off and put a carryhandle on it and still had to crank my sights all the way over to the right.  I re-indexed my barrel and even with a slight cant going the other way I was just barely able to zero at 25m on an 8 inch circle.  I'm not sure Stag will want to take a look at my barrel after I re-indexed and probably voided warranty, however, my barrel is F'd.  Also when looking at the end of the barrel the hole does not look like a circle and some copper is building up on that part of the crown that does not look machined well.  I put the ARMS on my Bushmaster and works fine.  Two different sights on my Stag upper and not well.  I ended up ordering a Wison barrel but have to wait for now.

SFC