I made some walnut vise jaw covers years ago and have used the hell out of them. I don't mess with muzzle attachments often, but when I do, I grab the gas block/sight base with the wood jaws and it always works. Haven't turned a gas block yet. The worst one I have encountered was a CMMG heavy barrel with an A2 FH. I finally had to heat it, then do the old plumber's trick of pushing first in the tightening motion, then pulling in the loosening motion. That did it but I was using so much torque that the HBAR was visibly springing. Still shot fine so I guess no harm. I installed that little Strike Ind. 'Warhog' short brake (discontinued) and it works great. I wanted the rifle to be as short as possible and with a comp for getting back on target quicker with an ACOG.