Warning

 

Close
Confirm Action

Are you sure you wish to do this?

Cancel Confirm
AR15.COM
AR Sponsor
4/4/2007 12:25:16 PM EDT
What could cause flyers going straight right anywhere from 3 to 6 inches and then having a 1/2 to 3/4 inch group?

I have a friend that built an upper and told me he was having problems.  He brought it over and I took it all apart and re-assembled it and it is still doing it.  It's built on a CMT upper with LT handguards and a SS barrel.  
4/4/2007 5:13:07 PM EDT
[#1]
Barrel getting too hot and over whipping/harmonics changing,

Bullet strikes to the FS or the barrel twist not fast enough to stablize heaver bullet types,

Barrel nut loose, and barrel moving in the upper barrel socket,

Change in ammo types.
4/4/2007 7:40:44 PM EDT
[#2]
Not the barrel getting hot.

It's a 1/7 so twist is fine and we've tried it with 55 and up to 75 with no change.

I took it apart and re-torqued everything to spec so it's not a loos barrel nut.

He had a brake on it instead of a flash hider and it was pretty dirty on the first baffle but not enough to effect it I wouldn't think.

That was the only thing I thought might be a possibility.  Or something is jacked up internally on the barrel.
4/5/2007 4:21:17 AM EDT
[#3]
CLP (teflon) in the bore, and not shot out yet (takes about twenty shots to burn the teflon of the bore).
AR Sponsor