Hello, I have a newly built "AR10" .308 but have some 'short stroke' issues like many new AR308 owners seem to.  I think the culprit is under-gassing.  The upper was complete upper from aero precision but I suspect the gas block was not perfectly aligned (it was directly butted against the shoulder).
I took the muzzle device and GB off.  There was signs of gas leak. Centering the gas port using the set screw I estimate the GB needs about .010-.015" relief forward of the shoulder using a feeler gauge for it to line up dead center on the port.  

Since I have it apart right now and I don't feel like playing guessing games, I figure now is a good time I could have the gas port size verified/reamed if anyone either recommends a good gunsmith in the area OR if a fellow local forum member has some time and tools and wants to make a few bucks or case of beer...  Perhaps have the barrel dimpled for ensured alignment and check headspace just in case the toolcraft bcg isnt playing nicely with the aero precision upper before i start buying new adjustable gas blocks and changing up buffer systems to try and adapt.

Thanks!
Mo