Bear Creek Arsenal "Irithyll" AR-15 AR Pistol Barrel 7.5" Contour Barrel 1-7 Twist 5.56 NATO Manganese Phosphate Finish

Bear Creek Arsenal Irithyll 7.5-Inch 5.56 NATO AR-15 Pistol Barrel

The Bear Creek Arsenal Irithyll 7.5-Inch AR-15 Pistol Barrel features 4150 Chrome Moly Vanadium construction with manganese phosphate finish. This contour profile barrel is chambered in 5.56 NATO with a 1:7 twist rate and pistol-length gas system compatibility. The barrel includes a nitride-finished barrel extension, 0.75-inch gas block shelf, and 1/2x28 thread pitch for muzzle device attachment.

Key Features

• 4150 Chrome Moly Vanadium steel construction
• Manganese phosphate finish with nitride barrel extension
• 7.5-inch length, contour profile
• 5.56 NATO chamber, 1:7 twist rate
• Pistol-length gas system, 0.75-inch gas block shelf
• 1/2x28 thread pitch for muzzle devices
• Free-float handguard compatible

Perfect For

• Compact AR-15 pistol builds requiring short barrel length
• Shooters prioritizing stabilization of heavier 5.56 NATO projectiles
• Builders seeking Bear Creek Arsenal quality at pistol length
• Users assembling free-float handguard configurations

Contour Profile Construction

The contour profile provides weight distribution across the 7.5-inch barrel length while maintaining structural integrity for pistol-length gas system operation. The 4150 Chrome Moly Vanadium steel construction offers material strength for the pressures generated in 5.56 NATO chambering. The manganese phosphate finish covers the exterior barrel surface.

1:7 Twist Rate Stabilization

The 1:7 twist rate provides stabilization for heavier projectile weights in 5.56 NATO ammunition. This twist rate completes one full rotation every 7 inches of barrel length, offering compatibility with projectiles ranging from standard 55-grain to heavier 77-grain bullets. The twist rate matches military specification for 5.56 NATO chambering.

Pistol-Length Gas System Compatibility

The barrel features a 0.75-inch gas block shelf diameter and pistol-length gas system port location. This configuration pairs with pistol-length gas tubes and low-profile or standard gas blocks measuring 0.75 inches in diameter. The 1/2x28 thread pitch at the muzzle accepts standard AR-15 muzzle devices including flash hiders, brakes, and compensators.

Follow safe handling and manufacturer instructions. Ensure compliance with all applicable federal, state, and local laws.