This BCA AR-15 Barrel is a 16" government profile barrel made of 4150 chrome moly vanadium steel with a black nitride finish, a carbine length gas system with a 1:8 twist rate. The barrel is chambered in 5.56 Nato and machined with M4 feed ramps in the barrel extension. All Finished Barrels go through a 100% Inspection Process. Inspections Equipment includes CMMs and Air Gauges for the Bores. BCA's expectations are that our Barrels, 16 inches or longer, will hold a 1.000" MOA at 100 yards with appropriate ammo and shooting techniques.