The GLFA AR10 rifles barrels have 5R rifling, as well as being double thermally stress-relieved and air-gauged. The heavy barrel incorporates a rifle-length gas tube, with 0.750 Gas Block. The barrel is threaded in 5/8"x24 and is fitted with a ported compensator hand tightened to the firearm. Each barrel is surrounded by a 15.25" aluminum M-Lok handguard with a disrupted picatinny rail on top, allowing you to both attach the different accessories you may require and C-clamp the weapon to help increase stability.