Gunsmithing DPMS Mk12 w/ windage prob

[JOct1]

I have a DPMS upper that literally shoots so far to the left that iron sights run out of right windage adjustment as close as 25 yards and scopes @ 100 yards can barely get on the left side of the paper. Had a respectable gunsmith break it down since the Surefire MB was originally mounted incorrectly/tilted to left and all who shot the rifle (5 in total with same results) thought this was the problem. Had 'smith check threads, barrel, gas tube, quad rail mounting and even stake the carrier key screws, etc. as well as remount MB. Upper still prints the same, far left, out of two different lowers and with both BUIS, a Trijicon Accupoint (ran out of wimdage @ 100) and TA01NSN ACOG. Any ideas? (note: While the DPMS was @ the shop, I picked up a LaRue Stealth upper. No problems when mounted on either lower).

 

[Outsydlooknin75]

Re: DPMS Mk12 w/ windage prob

Sounds to me like the front of the upper isnt true and is cocking the barrel to one side ..... I would send it back to DPMS and tell them to fix it.