Bushmaster 0040017BLK QRC Complete Upper 5.56x45mm NATO 16" Black Nitride Barrel, Aluminum Black Hard Coat Anodized Receiver, M-LOK Handguard for AR-15

The Bushmaster 0040017BLK QRC Complete Upper 5.56x45mm NATO 16" Black Nitride Barrel is a drop-in AR-15 upper receiver assembly engineered for law enforcement, military, and civilian tactical operators who demand reliability without compromise. This complete upper eliminates the need for gunsmithing or bench assembly—it attaches directly to any standard AR-15 lower receiver with a single takedown pin, making it ideal for operators building a rifle quickly or adding a versatile 5.56 NATO platform to an existing inventory. The QRC designation reflects Bushmaster's commitment to delivering field-ready components that meet the durability standards of professional end-users.

Built around a 16-inch black nitride barrel, this upper delivers the velocity and ballistic consistency required for duty work while maintaining a compact 28.5-inch overall length suitable for vehicle operations and confined spaces. The black nitride finish provides superior corrosion resistance and durability compared to standard parkerizing, critical for operators in salt-air or high-humidity environments. The aluminum receiver features hard-coat Type III anodizing for maximum wear resistance, and the integrated M-LOK handguard gives shooters a lightweight, modular platform for mounting lights, lasers, vertical grips, and other tactical accessories without rail cuts or proprietary interfaces. At 4.28 pounds, this upper remains agile in the hands while maintaining the mass necessary for recoil management and sustained accuracy during high-round-count drills.

This complete upper is compatible with any AR-15 lower receiver chambered in 5.56x45mm NATO or .223 Remington, making it an economical choice for agencies standardizing platforms or operators expanding a modular rifle system. Law enforcement SWAT teams, military support elements, and civilian shooters running three-gun or tactical carbine courses benefit from the plug-and-play design and proven Bushmaster manufacturing pedigree. Installation requires no special tools beyond a standard takedown pin punch; simply align the upper with your lower, insert the pin, and the rifle is ready for duty or range use. The M-LOK handguard accepts industry-standard accessories from manufacturers like Magpul, Midwest Industries, and Surefire, ensuring your configuration grows with your mission requirements.