I've tried to do my research, but the newest info I could locate was from Magwa's post 3 years ago. I'm putting together a "dissy" on a DPMS G2 MOE with a .750 barrel mating surface. I'll be running the MI 15" MLOK rail, and I want to use an adjustable gas block. I know I don't need to use one, but I want to. The MI rail has a 1.3" inside diameter, with a .4" gas tube channel. So far, I see the SLR Sentry 7-S set screw will fit, as will the Seekins Precision Low Profile Adjustable (thanks to info from Wash ). The SLR Sentry 7-S has a distance from bottom of the barrel to bottom of the block of .17" and the Sentry 7-C clamp on has a distance of .21" for the same measurement. Interestingly (to me, anyway) SLR recommends using the 7-C only for rails with an ID of 1.35" or larger and the 7-S for anything smaller. I'd prefer to use a clamp on block if I can so I don't have to worry about the existing A2 block pin grooves and the set screws of the new block. Also, I don't have a drill press and I'd hate to f-up the barrel with a hand drill.
So, anything anyone can suggest would be welcome. Thanks!