The ATI Mil-Sport is an AR-style semi-automatic rifle chambered in .300 AAC Blackout with a 16-inch threaded barrel. It has a black synthetic stock and a 15-inch M-Lok handguard, and ships with a 30-round magazine. 
 

Key Specifications 

• Brand: ATI 
• Model: Mil-Sport 
• Caliber: .300 AAC Blackout 
• Action: Semi Auto 
• Capacity: 30 
• Barrel Length: 16 inches 
• Color/Finish: Black 
   

Detailed Features 

• 16-inch threaded barrel 
• 15-inch M-Lok handguard 
• Black synthetic stock 
• AR-pattern semi-automatic platform 
• 30-round magazine included

Owners of the ATI Mil-Sport in .300 AAC Blackout tend to view it as a budget-accessible entry into the .300 Blackout platform. The M-Lok handguard and threaded barrel give it practical upgrade paths without paying a premium upfront.

Shooting impressions are generally in line with expectations for the price tier. Reliability with supersonic ammunition is reported as solid; some owners note a preference for ensuring proper suppressor-ready loads with the threaded muzzle. The 15-inch M-Lok rail draws consistent praise for its length and accessory compatibility.

On value, the Mil-Sport competes well in the entry-level AR segment. The trigger is the most commonly cited weak point, with many owners swapping it early. Build tolerances are acceptable to most, though a minority report needing a break-in period before cycling was fully consistent.