The Colt LE6945CK Upper Receiver Conversion Kit (brand part no. LE6945CK) is a complete, one-piece monolithic upper assembly chambered in 5.56 NATO with a compact 10.3-inch barrel, built to Colt’s law-enforcement model-line specification. Colt machines this upper as a single unitized receiver group rather than a separate upper and rail system, giving it exceptional rigidity for mounted optics, and finishes it in matte black to match standard AR-15 lowers. The 1:7 twist stabilizes the full range of 5.56 NATO bullet weights. It is sold as an upper only, with no lower receiver included. Among our AR15 uppers, this Colt conversion kit suits builders who want a genuine Colt monolithic upper without buying a complete rifle.

Key Specifications

• The chambering is 5.56 NATO.
• The barrel is 10.3 inches long.
• The rate of twist is 1:7 inches.
• The upper is a monolithic, one-piece receiver design.
• The upper ships as a complete assembly.
• The finish is matte black.

Frequently Asked Questions

What twist rate does the barrel use? A 1:7 twist, which stabilizes the full range of 5.56 NATO bullet weights.

Does it include a lower receiver? No. It ships as a complete monolithic upper assembly only, with no lower receiver included.

What makes it “monolithic”? The upper receiver and rail are machined as a single unitized piece rather than assembled from separate parts, giving a more rigid optics-mounting platform.

Buy the Colt LE6945CK Upper Receiver Conversion Kit

A genuine Colt monolithic upper built to a proven law-enforcement spec, the LE6945CK gives builders a rigid, compact 5.56 platform without a full rifle purchase. Order it from our Lubbock, Texas gun shop for fast shipping.