S7 tool steel M16 carrier with a four-position gas vent adjustable through the ejection port. Tunes carrier velocity for suppressed rifles and cycling-sensitive builds.


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Bootleg Inc AR-15 Four Position Adjustable Carrier, Complete, Retail Packaging, Black, BP-C15-D
The Bootleg Inc Four Position Adjustable Carrier builds gas regulation into the bolt carrier itself. A rotating vent on the side of the carrier vents excess carrier gas and regulates carrier velocity, working like an adjustable gas block that lives inside the receiver. The result is control over carrier velocity without changing buffers, buffer springs, or a gas block, which is the reason it earns a spot in suppressed and tuned AR-15 builds.
Four settings cover the full range. The Unsuppressed position vents the least gas for standard shooting, the Suppressed position sits 180 degrees opposite and vents the most to fight the extra back pressure a can adds, and two intermediate stops let you fine-tune for a specific rifle's gas port and barrel length. Adjustments are made through the ejection port with the rim of a spent shell casing, so a shooter can retune between suppressed and unsuppressed strings without pulling the carrier or reaching for a tool. An adjustment pin lifts out for cleaning.
The carrier is machined from S7 tool steel, a shock-resistant grade suited to the high-frequency, high-temperature cycling an AR carrier sees, and wears a Lithium Isonite salt-bath finish that resists carbon fouling and wipes clean. It runs the M16 full-auto profile and is full-auto rated, ships as a complete bolt carrier group with a 9310 steel bolt, and the bolt is high-pressure tested and magnetic-particle inspected. Because it puts a gas adjustment inside the carrier, it is also a tuning tool for cycling-sensitive builds such as forced-reset-trigger rifles, where dialing carrier speed to the ammunition and barrel drives reset consistency.

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Add the Bootleg Inc Four Position Adjustable Carrier (BP-C15-D) to your build and see how it enhances your platform.