The TacFire BU-556-5 Pistol Upper Assembly is built for reliability and performance in 5.56x45mm NATO, featuring a 5-inch black nitride barrel paired with a black anodized 7075-T6 aluminum receiver and a robust M-LOK handguard for versatile mounting options. This complete upper ships with a bolt carrier group, delivering a ready-to-install solution for AR-platform pistols that prioritize quick handling, enhanced maneuverability, and consistent gas performance at the range. The compact 5" barrel length provides a balanced profile ideal for compact builds, CQB scenarios, and dynamic field use, while the nitride finish protects against wear and corrosion under demanding shooting conditions. The black anodized receiver offers a durable, low-profile aesthetic that pairs well with a wide range of optics and accessories, and the optic-ready design without built-in sights allows you to tailor your setup to your preferred sighting system. Ideal for upgrade projects or custom builds, this TacFire upper assembly enhances reliability, reduces setup time, and supports precision shooting with a streamlined, mid-length AR platform solution.