06-06-2013, 07:41 PM
I wouldn't go shorter than 18" on rifle-length gas.
Adjustable gas blocks are primarily for overgassed systems. The concern with going shorter than 18" is not enough gas to cycle the action reliably. A malfunctioning AR doesn't usually perform to its accuracy potential. You would likely have to enlarge the gas port if cut to 16", but that's an inexact science with the muzzle and gas port so close together. And I don't recommend relocating the gas port either.
Go 18" and be happy.
Adjustable gas blocks are primarily for overgassed systems. The concern with going shorter than 18" is not enough gas to cycle the action reliably. A malfunctioning AR doesn't usually perform to its accuracy potential. You would likely have to enlarge the gas port if cut to 16", but that's an inexact science with the muzzle and gas port so close together. And I don't recommend relocating the gas port either.
Go 18" and be happy.
Drifter