ok my buddy bought a 18" stainless bull free float CMMG upper in about 2012. Complete factory free float varmint upper When he first got it it was short stroking. We took it down and it appeared that the gas block was not centered on the gas port when the sxrew was cinched into the dimple. Do you think it is likely that the dimple was indexed improperly? That is kind of what we thought but now looking back, they had to have used a jig right? That makes me wonder if maybe it was just a misalignmmet of the block.
How woild you go about fixing this?
How woild you go about fixing this?