Rosco Manufacturing Bloodline AR-15 5.56 NATO 16" Heavy Barrel - Nitride

The Rosco Manufacturing Bloodline 16" Heavy Barrel is a 5.56 NATO chambered, heavy profile drop-in barrel designed for the AR-15 platform. Cut from 4150 Chrome Moly Vanadium steel and finished in black Nitride, it is purpose-built to handle sustained fire, hard training cycles, and full-auto use.

The 16" heavy contour adds rigidity and increases thermal mass compared to lighter M4 and government profiles, making this barrel a natural match for duty carbines and hard-use training rifles. The finished barrel weighs approximately 35.76 oz. A 1:7" twist rate stabilizes the full range of 5.56 NATO projectile weights, from light varmint bullets up through heavy 77gr open-pattern match and duty loads.

This Bloodline is set up for a carbine-length gas system and is threaded 1/2x28 to accept standard 5.56 muzzle devices. The Nitride surface treatment hardens both the bore and the exterior for improved corrosion resistance and wear life over traditional phosphate, while keeping the outside profile clean and consistent.

Whether you are assembling a new hard-use carbine or replacing a worn barrel on an existing AR-15, the Rosco Bloodline 16" Heavy Barrel delivers the durability and proven geometry that defines the Bloodline line.