EDEMO Diamondback Barrels AR-15 Nitride Barrel 10in .300BLK 1-8 Twist Rate 5/8 X 24 TPI 300P10H50B8 EDEMO4 Used Condition Fair. This barrel is machined from 4150 Chrome Moly Vanadium Steel and features 5R rifling to ensure consistent accuracy and has a...