Cmmg Rifle Receiver Ext/stock Kit

The CMMG Rifle Receiver Extension/Stock Kit is a complete A1-style receiver extension assembly designed to streamline AR-15 lower assembly builds. This kit combines essential components—rifle-length receiver extension tube, buffer, buffer spring, A1 fixed stock, end cap, and stock screw—into a single integrated package, eliminating the need to source multiple parts from different vendors. For shooters building a rifle from a 80% lower or completing a partially finished receiver, this kit provides a proven, field-tested solution for the rear end assembly.

The rifle-length extension tube and matched buffer system are sized for standard rifle cartridges and deliver consistent recoil impulse management across calibers like 5.56 NATO and .308. The fixed A1-profile stock offers a compact, no-nonsense design familiar to military and law enforcement operators—reliable, robust, and free from the maintenance requirements of adjustable stock mechanisms. All components are engineered to MILSPEC dimensions, ensuring compatibility with standard lower receivers and trigger guard assemblies. Weighing 1.44 lbs, the kit adds minimal mass to your build while maintaining the structural integrity required for high-round-count training and duty use.

This receiver extension kit is ideal for home builders, armorer-level gunsmiths, and operators looking to establish a clean, simple rifle platform without unnecessary features or complexity. It serves bolt-action conversions, competition builds, patrol rifles, and training platforms equally well. When paired with a quality lower parts kit and matched upper receiver assembly, the CMMG kit delivers a field-ready backbone that meets or exceeds the durability standards expected in professional and recreational shooting environments.

CMMG manufactures direct for the AR platform market, and this receiver extension assembly reflects the brand's commitment to MILSPEC compliance and interchangeability. The kit reduces build time and eliminates guesswork about parts fitment, making it a practical choice for first-time builders and experienced shooters alike.