16 inch with a comp on the end would be same as an 18, more or less. But less jump by far.
You are long tube gassing them? Gotta be smoother etc... as you well know, I know 20 inch guns and gas systems, the rest I do not know...
BTW, side note, bought a bolt in 300 whisper, and still will buy that gas block you noted for my AR in 300 whsiper, its just on the back burner now till the bolt gun is finished and I get back from annual fall AK hunt and see how much I have left... AT least now I"ll be gassing the AR to function, not to not function.
