AR-15 5.56 Cal Complete Upper Kit (Micro Pistol Length) (Compression M-LOK Hg) (Mini Muzzle Brake)

Description

This AR-15 5.56 Cal Complete Upper Kit (Micro Pistol Length) provides a comprehensive set of US-made components for building a custom upper receiver. Designed for experienced builders, the kit includes all essential hardware to assemble a functional platform without requiring additional sourcing for standard parts. The assembly remains unassembled, allowing for tailored configuration during the build process.

The core of this kit is the 5.5″ 5.56mm 1:5 Twist Contour 4150 Barrel, which provides the necessary length and twist rate for reliable feeding. This barrel is paired with a Steel Low Pro .750 Gas Block and a Custom Short Gas Tube, ensuring proper gas system timing for the compact configuration. The 5.56 Complete BCG, Forward Assist Assembly, and 5.56 Charging Handle are included to complete the internal mechanism.

For external mounting and protection, the kit features a US 4″ M-LOK Compression Handguard With Barrel Nut & Hardware (GT-4ALC). This handguard offers M-LOK slots for accessory attachment while maintaining a compact profile suitable for pistol-length builds. The assembly is terminated with a 1/2 X 28 Mini Muzzle Brake (1326-MB-P-MINI), secured with a 1/2 X 28 Crush Washer, to manage recoil and muzzle rise. The 5.56 Ejection Door Assembly (Gen 3 Gate) and 5.56 Upper Receiver round out the package, providing the structural foundation and ejection functionality.

Constructed from durable materials, the upper receiver and handguard utilize aluminum construction for strength and weight management. All components are manufactured in the United States, ensuring consistent quality and adherence to domestic production standards. This kit is ideal for builders seeking Cal Complete, US-made foundation for a 5.56-caliber AR-15 pistol or compact upper, with the flexibility to customize the final assembly to specific operational requirements.