This CMMG AR-15 Gunbuilder’s Lower Parts Kit supplies the common components needed to assemble an AR-15 lower receiver while omitting frequently upgraded items. It is intended for users assembling or customizing a lower receiver and is built to meet or exceed mil-spec standards where specified. The kit does not include the pistol grip, fire control group (trigger and hammer), or trigger guard.
Key Specifications
- The kit is designed for AR-15 lower receivers.
- The finish is listed as Black Matte.
- The kit material is specified as Various, with frame material listed as Steel.
- Included hardware references list Bolt catch and roll pin among supplied items.
- Included hardware references list Bolt catch plunger and spring as supplied components.
- Included hardware references list Trigger and hammer retaining pins as supplied parts (fire control components themselves are not included).
- Included hardware references list Safety selector, detent and spring as provided items.
- Included hardware references list Magazine catch, spring, and release button as provided items.
- Package dimensions are listed as 0.95 x 3.95 x 7.80 (units not specified in source data).
This kit is focused on the lower receiver build and supplies the common pins, detents, and catch components that most builders need while leaving the fire control group, trigger guard, and pistol grip for the builder to select. Parts are described as meeting or exceeding mil-spec where noted, making this a practical choice for custom builds or repairs where the builder prefers to choose their own fire control components and grip ergonomics.
Product information is supplied by the manufacturer and/or distributor and may be automatically formatted or enhanced using AI for clarity and consistency. While we strive for accuracy, specifications, features, and included items may change without notice. Always verify details using the manufacturer’s official documentation and the information shown on this product page before purchase or use.
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