Luth-ar BL-11-7 5.56mm 11.50" Button Broached Black Phosphate Chrome Moly Vanadium Fits AR-15
4150 Chrome Molly Vanadium 5.56 mm, button broached barrel. The barrel is threaded with a 1/2x28 thread pitch, a 1-7 RH twist rate with 6 lands and grooves and an M4 feed ramp. This barrel takes a .750 gas block.