The barrel is one of the most critical components of your build. We only offer high quailty barrels so you can be confident that your rifle will be off to a good start with which ever barrel you decide on.Features: 16" Cold Hammer Forged Barrel DIN 21CrM0V511 Chrome Lined 1/7 Twist Rate 5/8 X 24 Thread Pitch for Muzzle .300 Black Out Chamber .750 Gas Block Seat M4 Barrel Extension Mil-Spec Phosphate Coating Carbine Gas Weight: 2lb