SKU: 138482
UPC: 604206918222
MPN: 0040004BLK
The Bushmaster 0040004BLK M4 Patrolman's Upper 5.56x45mm NATO is a combat-proven upper receiver assembly built for law enforcement patrol rifles, tactical operations, and serious civilian shooters who demand reliability under pressure. This complete upper—featuring a 16-inch barrel, aluminum receiver, and integrated handguard—delivers the accuracy and handling characteristics that have made the M4 platform the standard across U.S. military and police forces for over two decades. Whether you're outfitting a duty rifle, building a patrol carbine, or upgrading an existing AR platform, the Patrolman's Upper provides the core components needed for immediate deployment.
At the heart of this upper is a 16-inch black nitride barrel—a professional-grade finish that resists corrosion and reduces glare in tactical environments while maintaining a durable, low-maintenance surface ideal for duty use. The receiver is machined from 7075-T6 aluminum, a high-strength aerospace-grade alloy that withstands the rigors of continuous fire and field deployment without unnecessary weight penalty. The M4 handguard provides a conventional platform for mounting accessories such as tactical lights, laser systems, and vertical grips—essential for low-light responses and room-clearing operations. At 5.18 pounds, this upper balances control and maneuverability without compromising structural integrity or accuracy potential.
The Bushmaster upper is compatible with any AR-15 platform lower receiver, making it an ideal upgrade path for existing rifle owners or a standalone component for custom builds. Law enforcement agencies, security professionals, and recreational shooters who run intermediate-distance targets or home-defense configurations will find this upper's 16-inch length strikes the optimal balance between velocity (sufficient for 5.56 NATO ballistics), handling speed, and accuracy. Installation requires only assembly to your choice of lower receiver—no gunsmith work necessary. This is professional-grade hardware designed to run, and run hard, in the conditions where AR-platform rifles are trusted most.
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Bushmaster
