Faxon Duty Series 13.9" Gunner 5.56 NATO 4150 Nitride Mid‑Length Barrel

Faxon Duty Series 13.9″ Gunner 5.56 NATO 4150 Nitride Mid‑Length Barrel

The Faxon Duty Series 13.9″ Gunner barrel is designed for shooters seeking the perfect blend of compact maneuverability and precision accuracy in a mid‑length AR‑15 platform. Forged from premium 4150 chromium moly vanadium (CMV) steel and treated inside and out with a QPQ salt‑bath nitride finish, this barrel offers unmatched corrosion resistance and surface hardness, ensuring consistent performance even during high‑round counts. Its Gunner profile balances the rigidity of government‑profile barrels with the weight savings of pencil contours, reducing barrel whip and harmonics for tighter groupings.

Chambered in 5.56 NATO, the rifling features a 1:8 twist rate to stabilize a wide range of bullet weights—from 55‑grain varmint loads to 77‑grain match projectiles—delivering reliable downrange ballistics. The mid‑length gas system with a .625″ gas block journal smooths recoil impulse and optimizes dwell time, making it ideal for both unsuppressed and suppressed builds. The precision‑machined 1/2×28 TPI muzzle thread accommodates brakes, compensators, or suppressors, while the M4 feed‑ramp extension ensures consistent lockup in Mil‑Spec uppers.

Weighing just 1.22 lbs and measuring 13.9″ in length, this barrel keeps the front end agile without sacrificing stiffness. A recessed 11° target crown promotes uniform gas release and minimal muzzle disturbance, directly contributing to accuracy. Each barrel undergoes rigorous magnetic particle inspection (MPI) and air‑gauge testing to verify bore straightness and dimensions. Whether building a lightweight patrol carbine, a duty‑grade rifle, or a high‑speed competition rig, the Faxon 13.9″ Gunner barrel delivers the durability and precision your build demands.