Faxon Firearms Duty Series Features The Faxon Firearms Duty Series 16 inch barrel follows an authentic M4 profile balancing the rigidity needed for consistent accuracy with the maneuverability shooters expect from a general-purpose AR-15 barrel. A hard chrome-lined bore extends service life and reduces fouling buildup allowing the barrel to withstand sustained strings of fire better than an unlined counterpart. Built from certified 4150 CMV steel it meets mil-spec material standards chosen for strength and long-term consistency across demanding use. The carbine-length gas system ensures reliable cycling across a wide range of ammunition types and environmental conditions. Every Duty Series barrel undergoes MPI inspection air-gauge testing and headspace verification before leaving the factory giving builders confidence in both the metallurgy and precision of the finished part. The black chrome mag phosphate exterior finish provides mil-spec protection from corrosion and wear over years of service. At 16 inches with a 1/2x28 thread pattern this barrel accepts standard muzzle devices without additional machining. For shooters building a reliable military-style AR-15 for duty defense or range use this Faxon barrel delivers a proven tested combination of durability and accuracy. Faxon Firearms Duty Series Specifications Brand: Faxon Firearms Model: Duty Series Caliber: 5.56 NATO Length: 16 Color: Black Material: Chrome Moly Vanadium Finish: Chrome Mag Phosphate Barrel Type: Button Rifled Twist Rate: 1:7 Diameter: .750 Thread Pattern: 1/2x28 Weight: 1.22 lbs Gas System Length: Carbine Length Available At: GrabAGun