Davidson Defense Ronin Competition w/SBA3 Brace 8-inch 9MM Freefloat M-Lok Handguard Pistol Full Build Kit

Ronin Competition w-SBA3 Brace 8-Inch 9mm Freefloat M-LOK Handguard Pistol Full Build Kit

This is an AR-9 pistol full build kit chambered in 9mm, centered on an 8.3-inch medium profile steel barrel with a nitride finish, a 1-10 twist rate, and a direct blowback system with no gas tube or gas block. The 6061 billet pistol caliber AR-15 upper receiver with a black finish anchors the front end. The ACE-20 Series 7-inch freefloat M-LOK handguard in black covers the compact forend. An A2 GI Birdcage flash hider at 1-2x28 closes out the muzzle end. A 9mm nitride bolt carrier group in 8620 alloy steel with an external extractor and Glock and Colt pattern magazine compatibility, and a Mil-Spec M4 charging handle complete the upper side. The lower completion package covers a complete Mil-Spec AR-15 lower parts kit, a Mil-Spec heavy-duty AR-15 6-position buffer tube, an AR-15 9mm carbine buffer, a standard AR-15 carbine recoil spring, a Mil-Spec AR-15 and M16 receiver end plate, and an AR-15 carbine castle nut. An SB Tactical SBA3 adjustable pistol stabilizing brace in black closes out the rear end. Lower receiver not included.

Key Features

• 9mm chambering, 8.3-inch medium profile steel barrel, nitride finish
• 1-10 twist rate, 1-2x28 thread pitch
• Direct blowback operation, no gas tube or gas block
• 6061 billet pistol caliber AR-15 upper receiver, black
• ACE-20 Series 7-inch freefloat M-LOK handguard, black
• 9mm nitride bolt carrier group, 8620 alloy steel, external extractor, Glock and Colt pattern magazine compatible
• Mil-Spec AR-15 M4 charging handle
• A2 GI Birdcage flash hider, 1-2x28 thread pitch, black crush washer
• Complete Mil-Spec AR-15 lower parts kit
• Mil-Spec heavy-duty AR-15 6-position buffer tube
• AR-15 9mm carbine buffer
• Standard AR-15 carbine recoil spring
• Mil-Spec AR-15 and M16 receiver end plate
• AR-15 carbine castle nut
• SB Tactical SBA3 adjustable pistol stabilizing brace, black, Mil-Spec carbine buffer tube compatible

Perfect For

• AR-9 pistol builders who need everything above the lower receiver for a 9mm build
• Shooters pairing this kit with an existing stripped or complete AR-9 compatible lower receiver
• Builders who want an SBA3 brace and a complete 9mm AR-9 pistol component set with an ACE-20 Series M-LOK handguard covered in one kit

Upper Assembly

The 6061 billet pistol caliber AR-15 upper receiver with a black finish forms the core of the front end for the AR-9 platform. The 8.3-inch medium profile steel barrel brings a nitride finish and a 1-10 twist rate to the 9mm chamber, threaded at 1-2x28. This upper operates on a direct blowback system, meaning there is no gas tube or gas block present or required. The ACE-20 Series 7-inch freefloat M-LOK handguard in black surrounds the barrel along the compact forend with M-LOK slots across the handguard surfaces for accessory attachment and optics mounting.

Bolt Carrier Group and Charging Handle

The 9mm nitride bolt carrier group is machined from 8620 alloy steel with a nitride finish and features an external extractor design specific to the AR-9 blowback platform. It is compatible with both Glock and Colt pattern magazines, giving the build flexibility in magazine selection at the lower receiver level. The Mil-Spec M4 charging handle pairs with the BCG inside the upper receiver to complete the upper interior and finish the front end of the build.

Muzzle Device

The A2 GI Birdcage flash hider threads onto the 1-2x28 muzzle end of the barrel. The included black crush washer seats at the barrel shoulder and completes the muzzle hardware for this kit.

Lower Completion Components

The complete Mil-Spec AR-15 lower parts kit covers the full internal lower component group, including the fire control group, magazine catch, bolt catch, and all associated pins and springs. The Mil-Spec heavy-duty AR-15 6-position buffer tube, AR-15 9mm carbine buffer, and standard AR-15 carbine recoil spring form the buffer system at the rear of the lower. The Mil-Spec AR-15 and M16 receiver end plate and AR-15 carbine castle nut lock the buffer tube down cleanly at the rear of the lower receiver. The SB Tactical SBA3 adjustable pistol stabilizing brace in black fits over the Mil-Spec 6-position buffer tube and closes out the rear end of the build with an adjustable length of pull and an integrated arm strap for single-handed support.

Follow safe handling and manufacturer instructions. Ensure compliance with all applicable federal, state, and local laws. Lower receiver not included.