The CMMG Mk4 Stripped Lower Receiver (brand part no. 55CA102TNG) is a forged AR-15 lower built for shooters assembling their own rifle, finished in a Tungsten Cerakote to match or contrast a Mk4 upper. CMMG machines the receiver from 7075-T6 aluminum forgings to mil-spec dimensions, making it compatible with any mil-spec AR-15 lower parts kit and standard AR-15/M4-pattern magazines. As a stripped receiver, it ships without a trigger group, buffer tube, or stock, ready for the builder to finish to spec. Among AR15 lowers, this Mk4 receiver favors builders who want a mil-spec-dimensioned foundation in a distinct Cerakote finish.

Key Specifications

• Fits the AR-15 platform.
• Machined from forged 7075-T6 aluminum.
• Finished in Tungsten Cerakote.
• Built to mil-spec dimensions for compatibility with standard lower parts kits.
• Accepts standard AR-15/M4-pattern magazines.
• Sold as a stripped receiver, with no trigger group, buffer tube, or stock included.

Frequently Asked Questions

Is this a complete lower or a stripped receiver? It is a stripped receiver — no trigger group, buffer tube, or stock is included.

Will a standard AR-15 lower parts kit fit? Yes, it is machined to mil-spec dimensions and accepts any standard mil-spec lower parts kit.

Buy the CMMG Mk4 Stripped Lower Receiver

A mil-spec-dimensioned forged lower in a distinct Tungsten finish is exactly what this CMMG Mk4 receiver delivers. Order it from our Lubbock, Texas gun shop for fast, insured shipping to your FFL.