Faxon Firearms Duty Series Gunner Mid-Length 5.56 Barreled Upper Receiver - Suppressor Ready - 11.5"

Faxon's Duty Series 11.5-inch Gunner barreled upper delivers the same suppressor-first gas system architecture as the complete upper — mid-length gas on an 11.5-inch barrel, adjustable gas block, Plan B-compatible MuzzLok flash hider — as a barreled upper assembly for builders who are supplying their own BCG and charging handle.

The Faxon Duty Series 11.5-inch Gunner 5.56 Barreled Upper is a barreled upper receiver assembly chambered in 5.56 NATO, featuring an 11.5-inch Gunner profile barrel with mid-length gas system, a patented adjustable .625-inch 3-screw low-profile gas block, a mid-length stainless steel gas tube, a Faxon MuzzLok stainless steel Plan B-compatible flash hider (1/2x28, .250-inch bore), a 10.75-inch M-LOK free-float handguard, and an enhanced forged AR-15 upper receiver. BCG and charging handle not included.

The mid-length gas system on an 11.5-inch barrel is deliberate and unusual — most 11.5-inch 5.56 builds run carbine-length gas, which produces a faster, more abrupt bolt carrier velocity that becomes progressively more difficult to manage as suppressor-generated back pressure stacks on top of it. Mid-length gas spreads the dwell time over a longer port-to-muzzle distance, producing a slower, more gradual bolt carrier velocity curve that gives back pressure room to dissipate before the bolt carrier reaches its rearward travel limit. The result is a more controllable, tuneable starting point for a dedicated suppressed build. The patented adjustable .625-inch 3-screw gas block extends that tunability further: the shooter can reduce or increase the gas port opening to fine-tune ejection pattern, recoil impulse, and cycling reliability around their specific suppressor, ammunition, and buffer combination — adjustments that are otherwise impossible without replacing the gas block entirely. The MuzzLok Plan B-compatible flash hider at 1/2x28 gives the builder a direct suppressor mount path for Plan B and Atlas-mount cans without a separate adapter. The Gunner barrel profile balances front-end weight reduction against rigidity for the 11.5-inch length. The 10.75-inch M-LOK handguard covers the gas system and provides full-length accessory attachment. This is a barreled upper for builders who are selecting their own BCG and charging handle — everything else is done.

Caliber: 5.56 NATO. Barrel: 11.5-inch Gunner profile, mid-length gas. Gas block: adjustable .625-inch 3-screw low-profile (patented). Gas tube: mid-length stainless steel. Muzzle: Faxon MuzzLok Plan B-compatible flash hider, 1/2x28, .250-inch bore. Handguard: 10.75-inch M-LOK free-float. Upper: enhanced forged AR-15. BCG and charging handle: not included.

Mid-length gas on an 11.5-inch barrel provides a longer dwell time and more gradual bolt carrier velocity than carbine gas — the correct foundation for suppressed use where back pressure management determines shooting comfort and reliability. Adjustable gas block allows per-suppressor tuning without hardware changes. Plan B MuzzLok eliminates suppressor mount adapter requirements. Builder's upper — BCG and charging handle sourced separately.

The right barreled upper for builders assembling a dedicated suppressed 5.56 host around their own BCG and charging handle — mid-length gas timing, adjustable gas block, and Plan B suppressor mount readiness already done.