When you’re building a rifle you can count on, start with the best — the Bushmaster M4 Complete Lower. Designed for seamless compatibility with 5.56 NATO and .223 Remington uppers, this complete lower provides a durable, versatile, and ergonomic foundation for your next AR-15 project. Featuring a matte black finish, a collapsible M4 stock, and an A2 pistol grip, this lower is ready for action right out of the box.

Whether you’re upgrading an existing build or assembling a new rifle from scratch, the Bushmaster Complete Lower delivers the quality and dependability that serious shooters demand — all in a lightweight, rugged package.

Key Features

  • Fully Assembled: Ready to pin to any mil-spec compatible upper receiver for fast, reliable builds.

  • Collapsible M4 Stock: Adjustable length of pull for personalized fit and improved maneuverability.

  • A2 Pistol Grip: Provides a secure, ergonomic hold for better control during rapid or precise shooting.

  • Matte Black Finish: Tough, tactical appearance with a durable coating built for the range and field.

  • Lightweight Design: Weighs just 2 lbs, helping keep your finished rifle nimble and easy to handle.

  • 2-Position Safety: Simple and reliable selector for confident operation.

Specifications

Feature Details
Manufacturer Bushmaster
Model M4 Complete Lower
Family AR-15 Rifle Series
Caliber Compatibility .223 Remington / 5.56 NATO
Type Accessory – Lower Receiver
Finish Matte Black
Finish Type Black
Stock Collapsible / Folding M4 Stock
Grip A2 Pistol Grip
Weight 2 lbs
Safety 2-Position Safety Selector
Shipping Weight 2.95 lbs
UPC 604206203168
Manufacturer Part Number 00-20010-BLK