Brownells BRN-15 13.70" Railed Upper 5.56x45mm 1:7 Mid-Length no BCG&CH, Black

The BRN-15 upper receiver groups, manufactured in the United States with premium components, serve as an excellent foundation for your next build. To complete the assembly, select your preferred Bolt carrier group and charging handle. These upper receiver groups are equipped with a 5.56x45mm chambered barrel, finished with a nitride coating and available in various popular lengths. The barrels a redesigned with a gas block dimple, ensuring secure engagement of the rear gas block screw and are stress-relieved for enhanced durability. The M-LOK handguard is uniquely extended beyond the gas block, maximizing usable space. Anti-rotation tabs at the rear of the handguard engage with the upper receiver maintaining alignment with the receiver's picatinny rail. The handguard is secured with large dual screws that pass through a properly torqued barrel nut, preventing any forward slippage. Additionally, large vents are strategically positioned towards the rear to facilitate rapid cooling of both the barrel and handguard. 4150 chrome moly vanadium (CMV) barrel 5.56x45mm Caliber 1:7 rifling twist rate Thread specification - 1/2-28 muzzle A2 flash suppressor 7075-T6 forged upper receivers Anodized upper receiver with hardcoat finish M4 feedramps in upper receiver and barrel extension Barrels are designated as 5.56x45mm, 1:7 twist, 4150CMV SR Manufactured entirely in the United States