Screw the compensator about the barrel, Awareness tighten the comp, then again off until finally it can be sq. on the slide profile. eight months in the past I'm on the lookout for suggestions for a muzzle brake for my 9mm AR9 having a 16″ barrel. I plan to use https://beretta-m9-muzzle-brake21260.blogthisbiz.com/32694680/getting-my-beretta-m9-muzzle-brake-to-work