Remington Defense’s premier shotgun is now the R12 Tactical Shotgun. The R12 is the tactical version of the Remington Versa Max first introduced to the sporting market in 2010. The Versa Max’s main innovation is putting the gas ports both in the chamber and just forward of it, rather than much further down the barrel. The shells of longer cartridges block more gas ports than shorter ones, effectively regulating the gas system. A 3.5″ shells blocks all the gas ports except the ones just forward of the chamber, while a 2.75″ shells blocks none of the gas ports.FOLLOW GIRLS JUST WANNA HAVE GUNS ON FACEBOOK!