Hello members,

I need some help with my gunner 18" .308 barrel. When I shoot more than two or three shots, it begins drifting right. The following photo shows a string, shot at 100 yards, after I waited 15 minutes for the barrel to completely cool down. I shot the first one in the middle of the duct tape. I waited about 20 seconds and shot the next one to the right. After about 10 seconds, I shot the the 3rd and 4th, and after 10 seconds, I shot the 5th and 6th, all moving right. I get MOA in vertical but, obviously, not horizontal.

I put on another AR10 upper .308 barrel (a cheap no-name barrel) on the same lower on the same day, same rest, same bcg, and same loads, and I don't get the stringing problem.

When this first happened, I changed the scope, thinking it was the problem; but the drifting continued with a better scope. I am using 168gr SMK and 168gr Hornady HPBT and Lake City and Lapua brass; I have tried four different powders and even cheap 147 grain bullets. I am not getting pressure signs and loads are below maximum charges. It has an Aero Precision upper and toolcraft BCG. I have checked that nothing is touching the gas block, and the barrel nut was torqued and used locktite

FWIW, I own ten ARs and other rifles, and reload for 13 different cartridges. and can usually get MOA, even .5 MOA on all my AR pistols and rifles.

I have sent Faxon customer service two emails, and no response after two months. I have a one shot AR barrel.