Rosco 11.5" M4 Profile 5.56 NATO Bloodline Barrel - Carbine-Length Gas

Rosco 11.5" M4 Profile 5.56 NATO Bloodline Barrel - Carbine-Length Gas

Compact, rugged, and engineered for modern tactical applications, the Rosco Bloodline 11.5" M4 barrel is the ideal foundation for your next SBR or AR pistol build. Chambered in 5.56 NATO and machined from 4150 CMV steel, this barrel features a nitride finish for enhanced corrosion resistance and durability under high round counts.

Rosco’s engineering focuses on real-world performance—balancing dwell time, gas port sizing, and twist rate to optimize suppressed shooting, patrol carbines, and high-reliability platforms. Whether you're building for duty use or personal defense, this barrel delivers the precision and dependability demanded by professionals and enthusiasts alike.

Note: ALL NFA RULES APPLY when using this barrel in SBR or pistol configurations.

4150 CMV Steel Construction
Delivers high strength and heat resistance for sustained performance.

Nitride Finish
Provides corrosion resistance and a sleek, low-maintenance surface.

M4 Profile
Classic contour balances weight and rigidity for versatile use.

Carbine-Length Gas System
Ensures reliable cycling and smooth recoil impulse in short-barreled setups.

11° Target Crown
Enhances bullet exit consistency for improved accuracy.

1:7 Twist Rate
Ideal for stabilizing heavier projectiles and maximizing ballistic performance.

1/2x28 Threaded Muzzle
Compatible with a wide range of muzzle devices and suppressors.

Nitride-Coated Barrel Extension
Improves feeding reliability and resists fouling.

Optimized for Suppressed Use
Engineered with properly sized gas ports for balanced performance.

Specifications

• Chamber: 5.56 NATO
• Barrel Length: 11.5 inches
• Material: 4150 Chrome Moly Vanadium Steel
• Profile: M4
• Finish: Nitride
• Twist Rate: 1:7
• Gas System Length: Carbine
• Gas Block Journal: .750 inches
• Muzzle Threads: 1/2 × 28 TPI
• Crown: 11° Target Crown
• Barrel Extension Finish: Nitride
• Weight: 20.82 oz