Proof Research AR15 Barrel Features The Proof Research AR15 Barrel is built around PXT PROOF Exponential Twist a complete rethinking of conventional rifling geometry and twist progression. By dramatically reducing rifling lead angle and smoothing projectile engagement into the bore the design reduces engraving force and minimizes throat erosion over the barrel s service life. Less felt torque during firing means improved recoil control and the ability to stay on target more effectively between shots. In controlled testing PXT barrels have demonstrated significant increases in barrel life while holding to the accuracy standards expected from a PROOF barrel. Built in carbon fiber with a rifle length gas system the 16 6mm ARC barrel carries a 1:7.5 twist rate five grooves and a .750 gas journal diameter sized for standard AR15 components. The 5/8-24 threaded muzzle accepts a wide range of muzzle devices and the barrel arrives fully chambered and ready for installation making it a straightforward upgrade for a build or refresh. Carbon fiber construction keeps weight down on the front end of the rifle without sacrificing the precision PROOF barrels are known for. It is a practical option for shooters looking to refine a modern gas gun with next generation barrel technology. Proof Research AR15 Barrel Specifications Manufacturer: Proof Research Model: AR15 Barrel Caliber: 6mm ARC Barrel Length: 16 Barrel Material: Carbon Fiber Gun Platform: AR15 Twist Rate: 1:7.5 Gas System: Rifle Length Diameter: .750 Grooves: 5 Muzzle Thread: 5/8x24 Weight: 1 lb. 12 oz. Available At: GrabAGun