Davidson Defense Overwatch 10.5-inch Pistol-Gas 1:8 .300 BLK AR-15 M-Lok Pistol Complete Upper Build

Overwatch 10.5-Inch Pistol-Gas 1-8 .300 BLK AR-15 M-LOK Pistol Complete Upper

This is a complete AR-15 upper chambered in .300 AAC Blackout, built around a 10.5-inch HBAR profile steel barrel with a Parkerized finish and a 1-8 twist rate. The 7075-T6 aluminum upper receiver with a Type III hardcoat anodized finish, M4 feed ramps, a standard forward assist, and a .223 and 5.56 ejection port door with rod and spring anchors the front end. The pistol-length gas tube and micro low-profile steel gas block at .750 complete the gas system, and the 10-inch freefloat tubular aluminum M-LOK handguard with a suppressor ready profile and a 1.77-inch internal diameter covers the forend. A Steel Flash Can Design 4 in black oxide with a 5-8x24 thread pitch compatible with 9mm and .350 Legend closes out the muzzle end. A complete AR-15 bolt carrier group made in the USA compatible with 5.56, .223, .300, and .350, and a Mil-Spec M4 charging handle complete the upper component set.

Key Features

• .300 AAC Blackout chambering, 10.5-inch HBAR profile steel barrel, Parkerized finish
• 1-8 twist rate, 5-8x24 thread pitch
• Pistol-length gas system with pistol-length gas tube
• Micro low-profile steel gas block, .750
• 7075-T6 aluminum upper receiver, Type III hardcoat anodized, M4 feed ramps
• Standard AR-15 forward assist
• AR-15 .223 and 5.56 ejection port door with rod and spring
• 10-inch freefloat tubular aluminum M-LOK handguard, suppressor ready profile, 1.77-inch internal diameter
• Complete AR-15 bolt carrier group, made in the USA, 5.56, .223, .300, .350 compatible
• Mil-Spec AR-15 M4 charging handle
• Steel Flash Can Design 4, black oxide finish, 5-8x24 thread pitch, 9mm and .350 Legend compatible
• Black 5-8-inch crush washer

Perfect For

• AR-15 pistol builders pairing a complete .300 BLK upper with an existing lower
• Shooters adding a 10.5-inch pistol-gas .300 BLK upper to an AR-15 lower they already own
• Builders who want a BCG and charging handle included with a suppressor ready tubular M-LOK handguard and flash can in one complete pistol-length .300 BLK upper assembly

Upper Receiver and Barrel

The 7075-T6 aluminum upper receiver with a Type III hardcoat anodized finish and M4 feed ramps forms the core of the front end, with a standard forward assist and a .223 and 5.56 ejection port door with rod and spring built in. The 10.5-inch HBAR profile steel barrel brings a Parkerized finish and a 1-8 twist rate to the .300 AAC Blackout chamber, threaded at 5-8x24. The pistol-length gas tube and micro low-profile steel gas block at .750 run a pistol-length gas system along the 10.5-inch barrel. The 10-inch freefloat tubular aluminum M-LOK handguard surrounds the barrel and gas system along the forend with a suppressor ready profile featuring a 1.77-inch internal diameter that provides clearance for a compatible short suppressor mounted at the muzzle end of the barrel underneath the handguard. M-LOK slots along the handguard body provide accessory attachment across the full 10-inch length.

Bolt Carrier Group and Charging Handle

The complete AR-15 bolt carrier group is made in the USA and compatible with 5.56, .223, .300, and .350, making it a well-suited choice for this .300 BLK chambering. The Mil-Spec M4 charging handle pairs with the BCG inside the upper receiver to complete the upper interior. These two components complete the upper component set alongside the upper assembly, barrel, and handguard.

Muzzle Device

The Steel Flash Can Design 4 in black oxide threads onto the 5-8x24 muzzle end of the barrel with compatibility noted for 9mm and .350 Legend at this thread pitch. The included black 5-8-inch crush washer seats at the barrel shoulder and completes the muzzle hardware for this upper.

Follow safe handling and manufacturer instructions. Ensure compliance with all applicable federal, state, and local laws.