ATI MilSport Upper 300 Blackout 8.5" M-LOK

ATI MilSport Upper Receiver Assembly

The ATI MilSport upper receiver represents a practical, no-nonsense approach to modern rifle building. This complete upper assembly arrives ready to mate with your lower receiver, offering immediate functionality without compromise.

Key Features

Barrel & Ballistics

• 8.5" barrel in 300 Blackout caliber
• 1:8 twist rate for stable bullet performance across a wide range of projectile weights
• Black nitride finish for corrosion resistance and durability

Accessory Platform

• M-LOK handguard provides multiple mounting points along the fore-end
• Ample real estate for lights, lasers, vertical grips, and other tactical accessories
• Modular design allows customization to your specific needs

Muzzle Management

• A2 flash hider installed at the muzzle
• Reduces visible muzzle flash signature for improved shooting comfort and tactical awareness

Why Choose This Upper

The 300 Blackout cartridge excels in short-barreled platforms, delivering effective performance in both supersonic and subsonic loads. The 1:8 twist rate ensures reliable stabilization whether you're running lightweight or heavy projectiles. This makes the MilSport upper an excellent choice for home defense, hunting, or general shooting applications where versatility matters.

The M-LOK system has become the modern standard for accessory mounting, offering strength and ease of use. Whether you're building your first AR or adding to an existing collection, this upper delivers solid construction and practical features at a competitive price point.