Davidson Defense Left-Handed Ronin Competition SBR Ready 10.5-inch Carbine-Gas 1:8 5.56 NATO AR-15 Freefloat M-Lok Handguard Pistol Full Build Kit

Left-Handed Ronin Competition SBR Ready 10.5-Inch Carbine-Gas 1-8 5.56 NATO AR-15 Freefloat M-LOK Handguard Pistol Full Build Kit

This is a left-handed AR-15 pistol full build kit chambered in 5.56 NATO, centered on a Sandel 10.5-inch government profile cryogenically treated steel barrel with a phosphate finish, a 1-8 twist rate, and a carbine-length gas system. The Black Diamond Series left-handed slick side billet aluminum upper receiver with a black anodized finish anchors the front end with a left-hand ejection port and a clean slick side exterior that omits the forward assist and dust cover from the receiver body. The carbine-length stainless steel gas tube and micro low-profile steel gas block at .750 complete the gas system, and the ACE-20 Series 10-inch freefloat M-LOK handguard covers the forend. An A2 GI Birdcage flash hider at 1-2x28 closes out the muzzle end. A Davidson Defense premium left-handed M16 nitride bolt carrier group 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 6-position buffer tube, a standard AR-15 carbine buffer at 3 oz., a standard AR-15 carbine recoil spring, a Mil-Spec AR-15 and M16 receiver end plate, and a Mil-Spec AR-15 carbine castle nut. This kit ships without a brace, leaving the final rear end setup to the buyer. Lower receiver not included.

Key Features

• 5.56 NATO chambering, Sandel 10.5-inch government profile cryogenically treated steel barrel, phosphate finish
• 1-8 twist rate, 1-2x28 thread pitch
• Carbine-length gas system with carbine-length stainless steel gas tube
• Micro low-profile steel gas block, .750
• Black Diamond Series left-handed slick side billet aluminum upper receiver, black anodized, no forward assist, no dust cover
• ACE-20 Series 10-inch freefloat M-LOK handguard
• Davidson Defense premium left-handed M16 nitride bolt carrier group
• Mil-Spec AR-15 M4 charging handle
• A2 GI Birdcage flash hider, 1-2x28 thread pitch
• Black 1-2-inch crush washer
• Complete Mil-Spec AR-15 lower parts kit
• Mil-Spec heavy-duty 6-position buffer tube
• Standard AR-15 carbine buffer, 3 oz.
• Standard AR-15 carbine recoil spring
• Mil-Spec AR-15 and M16 receiver end plate
• Mil-Spec AR-15 carbine castle nut
• SBR Ready

Perfect For

• Left-handed AR-15 pistol builders who need everything above the lower receiver for a 5.56 NATO build
• Shooters pairing this kit with an existing stripped or complete AR-15 lower receiver configured for left-hand operation
• Left-handed builders selecting their own brace or stock for a custom 5.56 NATO pistol or SBR platform with a Sandel cryogenically treated barrel and purpose-built left-hand ejection slick side billet upper already covered

Upper Assembly

The Black Diamond Series left-handed slick side billet aluminum upper receiver with a black anodized finish anchors the front end with a left-hand ejection port and a clean slick side exterior profile that omits both the forward assist and dust cover from the receiver body. The Sandel 10.5-inch government profile cryogenically treated steel barrel brings a phosphate finish and a 1-8 twist rate to the 5.56 NATO chamber, threaded at 1-2x28. The cryogenic treatment is applied to the barrel steel as a process that addresses stress and grain structure within the metal. The carbine-length stainless steel gas tube and micro low-profile steel gas block at .750 run a carbine-length gas system along the 10.5-inch barrel. The ACE-20 Series 10-inch freefloat M-LOK handguard surrounds the barrel and gas system along the forend with M-LOK slots along the handguard body for accessory attachment across the full 10-inch length.

Bolt Carrier Group and Charging Handle

The Davidson Defense premium left-handed M16 nitride bolt carrier group is a purpose-built left-hand BCG designed to function with the left-handed upper receiver and eject cases from the left side of the build. 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 1-2-inch 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 6-position buffer tube, standard AR-15 carbine buffer at 3 oz., 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 Mil-Spec AR-15 carbine castle nut lock the buffer tube down cleanly at the rear of the lower receiver. The brace or stock selection is left entirely to the buyer, keeping the final rear end open for a custom setup.

SBR Ready

This kit ships without a brace and is intended for builders selecting their own final rear end setup. The Mil-Spec heavy-duty 6-position buffer tube and complete lower hardware are included, but the brace or stock is sourced separately by the buyer. The final rear end configuration is setup dependent and determined by the component the buyer selects.

Follow safe handling and manufacturer instructions. Ensure compliance with all applicable federal, state, and local laws. Ships without a brace. Do not attach a stock unless compliant with applicable laws. Lower receiver not included.