ATI MilSport AR-9 9mm Pistol, 5.5 in Threaded Barrel, Forged 7075-T6 Upper/Billet Lower, Free-Float KeyMod Handguard, Black, 31+1
This American Tactical MilSport 9mm AR pistol combines a compact 5.5-inch threaded 4150 steel barrel with a forged 7075-T6 flat-top upper and a billet 7075-T6 lower configured for Glock-pattern magazines. It features a slim, free-float KeyMod handguard with a continuous Picatinny top rail and standard AR controls. Made in the USA and finished in durable hard-coat anodizing, it comes with a 31-round translucent magazine.
Condition
Overall Condition: Very good condition, showing only light, superficial signs of prior handling or use.
Bore Overall Condition: Excellent - Clean, mirror finish, no signs of wear.
Bore Rifling: Excellent Rifling - Sharp lands and grooves.
Specific Condition Notes: Minor handling marks are present on exterior surfaces. See photos for close-up views.
What's Included
- 1x 31-round translucent extended polymer Glock-pattern magazine (packaging labeled 'GLK-18')
- American Tactical MilSport owner's manual
The MilSport AR-9 platform uses a straight blowback, semi-automatic action for 9mm Luger, offering a compact 5.5-inch configuration with a threaded muzzle. The barrel is 4150 steel and QPQ-nitride treated for durability and corrosion resistance.
The receiver set pairs a forged 7075-T6 aluminum flat-top upper with a 7075-T6 billet lower designed for Glock-pattern double-stack 9mm magazines. The upper includes an ejection-port dust cover and omits a forward assist. Both receivers wear a hard-coat anodized black finish.
A free-float, slim aluminum KeyMod handguard provides accessory mounting flexibility, while a T-marked continuous Picatinny rail runs the full length of the handguard. The rail section measures 7.0 inches and aligns with the flat-top upper. No sights are included.
Controls are familiar and straightforward: standard AR magazine release, a manual safety with a two-position selector marked SAFE/SEMI, and an A2-style polymer pistol grip. The pistol buffer tube is fitted with a receiver end-plate single-point sling loop.
Capacity is 31+1 with the included translucent extended polymer magazine. Receiver markings include AMERICAN TACTICAL • SUMMERVILLE, SC • MADE IN USA, along with MilSport and MULTI CAL identifiers.