CMMG 55BA556 Mil-Spec Lower Parts Kit Black AR-15/Mk3/LR-308

The CMMG 55BA556 Mil-Spec Kit delivers precision-manufactured components that transform stripped lower receivers into fully functional firearms. This comprehensive parts kit maintains strict military specifications while offering compatibility across multiple CMMG platforms including AR-15, Mk3, and LR-308 configurations.

What Makes This Different

CMMG's mil-spec tolerances ensure consistent fit and function across all components, eliminating the fitment issues common with mixed-manufacturer parts kits. Each component undergoes quality control testing to verify dimensional accuracy and material hardness. The kit includes genuine mil-spec trigger components rated for over 50,000 trigger pulls, significantly outlasting commercial-grade alternatives.

Key Features

• Complete mil-spec lower parts kit with all necessary components for assembly
• Black oxide finish on steel components for corrosion resistance
• Compatible with AR-15, CMMG Mk3, and LR-308 platform receivers
• Includes mil-spec trigger group with 4.5-6.5 lb pull weight
• Precision-machined safety selector with 90-degree throw
• Heat-treated steel pins and springs for extended service life
• Magazine catch assembly with reversible magazine release

Field performance demonstrates the reliability expected from military specification components. The trigger group maintains consistent break characteristics through temperature extremes and high round counts. Law enforcement agencies and competitive shooters rely on mil-spec components for their predictable performance under stress. The black oxide finish withstands exposure to cleaning solvents and environmental conditions without degradation.

Technical Specs

• Manufacturer: CMMG
• Model: 55BA556
• Finish: Black oxide on steel components
• Compatibility: AR-15, CMMG Mk3, LR-308 platforms
• Trigger Pull Weight: 4.5-6.5 pounds
• Material: Steel pins and springs, polymer grip components
• UPC: 815835012599
• Country of Origin: United States

This mil-spec kit provides the foundation for reliable firearm function at a competitive price point. CMMG's reputation for quality control ensures each component meets or exceeds military standards. Professional builders and first-time assemblers alike benefit from the precise tolerances and included instructions.