Luth-AR .223 / 5.56 NATO A3 flattop upper receiver — fully assembled and ready to bolt onto your AR-15 lower. Comes with the charging handle pre-installed so you can pair it with a barrel and BCG and have a functional upper without buying separate small parts.

The upper is precision machined from a 7075-T6 aluminum forging and finished in mil-spec hardcoat anodized black. The flattop rail runs 12 Picatinny slots for mounting a red dot, magnified optic, flip-up backup sights, or a carry handle. M4-type feed ramps are cut into the receiver face for reliable feeding with any modern AR-15 barrel extension.

Features:

• Material: 7075-T6 forged aluminum
• Finish: mil-spec hardcoat anodized, matte black
• Caliber compatibility: 5.56 NATO, .223 Rem, 300 BLK, 5.45x39, and most AR-15 cartridges
• Feed ramps: M4 cut
• Forward assist: installed
• Ejection port cover: installed
• Charging handle: included and installed
• 12-slot Picatinny flattop rail for optics and BUIS

Headspace any non-Luth barrel before live fire and check that the BCG locks into battery under spring pressure with a hand-cycle test before loading rounds. A drop of medium-strength thread locker on the gas-block set screws goes a long way toward keeping a budget build quiet on the rail.