M4 5.56 Complete Monolithic Upper Receiver Groups - M4 LE6940 Upper Group 16in With BCG And Sights
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Overview
The Colt M4 5.56 Complete Monolithic Upper Receiver Group combines a 16-inch barrel with a complete assembly designed for the AR-15 platform. This upper receiver features a monolithic design that enhances structural integrity and simplifies installation, making it ideal for builders looking for a robust and streamlined setup. Commonly found in tactical or general-purpose builds, this upper is well-suited for those seeking reliable performance in various shooting scenarios.
Specifications
M4 5.56 Complete Monolithic Upper Receiver Groups - M4 LE6940 Upper Group 16in With BCG And Sights
Available Merchants(5)
Prices checked
Stock Alert
September 2026 on GunPartPicker
Colt M4 5.56 Complete Monolithic Upper Receiver Groups - M4 LE6940 Upper Group 16in With BCG And Sights ranked #267 of the 615 upper receivers builders added on GunPartPicker in September 2026. Builders on GunPartPicker first added it to a build in March 2026.
It was hard to find in September 2026, in stock on only 7 of the 22 days we checked, and today none of the 5 retailers we track has it in stock right now. It dipped to $1,079 at Optics Planet for a stretch in September 2026, well under its usual $1,199.99, so sales do come around. Listed prices start at $939.28 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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