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Colt
Overview
The Colt M4 LE6921 Upper Group features a stripped assembly designed for the AR-15 platform, with a barrel length of 14.5 inches and chambered in 5.56 NATO. This upper receiver is specifically tailored for builders looking to create a lightweight and compact setup while maintaining the reliability and performance characteristics of the M4 design. It's commonly used in tactical and home defense builds due to its maneuverability and caliber versatility.
Specifications
M4 5.56 Upper Receiver Groups - M4 LE6921 Upper Group 14.5in Stripped
Build history on GunPartPicker
Builders on GunPartPicker first added the Colt M4 5.56 Upper Receiver Groups - M4 LE6921 Upper Group 14.5in Stripped to a build in April 2026.
It was out of stock everywhere we track for all of September 2026, and today none of the 2 retailers we track has it in stock right now. Listed prices start at $428.58 at BattleHawk Armory for when it comes back.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 37 retailers
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