Proof Research Barrel Features This PROOF Research pre-fit carbon fiber barrel is for the Ruger 10/22. The Ruger pre-fit barrels will arrive threaded chambered and ready for installation. By designing carbon fiber barrels specifically for the Ruger 10/22 Proof has made it easy for individuals to swap barrels on their rifle. Proof Research Barrel Specifications Barrel Length: 16 Barrel Material: Carbon Fiber Barrel Twist Rate: 1:16 Barrel Type: Threaded Brand: Proof Caliber: .22 LR Color: Black/gray Firearm Accessories Weapon Fit: Ruger 10/22 Muzzle Thread: 1/2x28