LMT Full-Auto Enhanced 5.56mm Bolt Carrier Group, Black

This LMT Defense bolt carrier group (brand part no. R-L7FB3) is machined for 5.56mm bolt face and carrier dimensions and built to LMT’s enhanced specification, using a full-auto-profile carrier body — the heavier, staked-gas-key carrier geometry originally developed for M4/M16-family rifles — inside a standard semi-automatic bolt and carrier assembly. The carrier’s profile does not by itself determine whether a rifle fires semi- or full-automatic; that’s governed entirely by the fire control group in the lower receiver, and this BCG functions exactly like any other semi-auto AR-15 bolt carrier group when installed in a standard, unmodified semi-automatic lower. This AR bolt carrier group is finished in black.

Key Specifications

• Bolt face and carrier dimensions machined for 5.56mm.
• Built to LMT’s enhanced bolt carrier group specification.
• Uses a full-auto-profile carrier body, the heavier M4/M16-pattern carrier geometry.
• Finished in black.

Frequently Asked Questions

Does a full-auto-profile carrier make my semi-auto rifle shoot automatically? No. Firing mode is controlled entirely by the fire control group in the lower receiver, not the bolt carrier’s external profile. In a standard, unmodified semi-automatic lower, this BCG functions as an ordinary semi-auto bolt carrier group.

Why use a full-auto-profile carrier in a semi-auto rifle? The heavier carrier mass and staked gas key are valued for durability and reliability, which is why many semi-auto AR-15 builders choose this carrier profile even without any full-auto function.

Buy the LMT Full-Auto Enhanced 5.56mm Bolt Carrier Group, Black

An enhanced, full-auto-profile BCG from LMT Defense is a durability upgrade for any standard semi-auto AR-15 build. Order this from a Lubbock, TX gun shop and our team will get your order processed right away.