Shaw Barrels AR-15 Barrel Features The Shaw Barrels AR-15 barrel is machined from 416R stainless steel in an HBAR heavy barrel profile then finished with a bead blast matte coating that provides a durable low glare surface. Chambered in .22 ARC the barrel uses a 1:7 twist rate to stabilize the heavier bullets this cartridge is designed to push at extended ranges. Spiral fluting cut along the barrel s length reduces overall weight without sacrificing the rigidity that the heavy HBAR profile provides helping the barrel resist heat induced stringing during rapid fire. The rifle length gas system and 18 inch barrel length are matched to extract full velocity potential from the .22 ARC cartridge. At the muzzle the barrel is threaded 1/2x28 accepting standard AR-15 muzzle devices and the gas block diameter is .750 inches with a dimpled gas journal for secure set screw retention. The feed ramp is cut to M4 specifications and the barrel requires a 6.5 Grendel Type II or ARC pattern bolt for proper headspacing though the bolt itself is not included. Weighing 2.20 pounds the barrel balances the stiffness of a heavy profile with manageable weight for an AR-15 rifle build. For a builder chasing long range accuracy from the .22 ARC cartridge this Shaw Barrels HBAR barrel is a precision option available for sale at GrabAGun. Shaw Barrels AR-15 Barrel Specifications Manufacturer: Shaw Barrels Caliber: .22 ARC Compatible Hosts: AR-15 Finish: Bead Blast Matte Material: 416R Stainless Steel Barrel Type: Rifle Length Twist Rate: 1:7 Thread Pattern: 1/2x28 Barrel Description: HBAR Profile Spiral Fluted Barrel Length: 18 Weight: 2.20 lbs Available At: GrabAGun