The Faxon Firearms Duty Series AR15 Barrel 9mm 1:10 Twist 4150 Nitride - 8.5" light tapered profile delivers factory-tested reliability for modern pistol-caliber carbine builds, designed for blowback operation and known for consistent performance under field and range conditions. Crafted from certified 4150 Mil-Spec steel and finished in QPQ nitride for durability, this barrel undergoes a meticulous testing sequence at every stage and is precision inspected for headspace with hardened gauges, ensuring repeatable accuracy and zero surprises in critical applications. The button-rifled 9mm Luger bore features a 1:10 twist, an 8.5-inch length, and a Colt & Glock compatible feed ramp interface, streamlining installation across compatible uppers while maintaining a compact yet capable profile. Its outer finish and internal geometry are optimized for reliability and ease of maintenance, with no gas system required thanks to blowback operation and a ready-to-use 1/2-28 muzzle thread for compatible brakes or suppressor adapters. Weighing approximately 0.81 pounds, this barrel combines balanced handling with a proven target crown design and a practical taper that supports accurate, repeatable performance in duty, training, or sporting contexts.