Davidson Defense Thumper 5" 45ACP AR-45 Pistol Build Kit, M-Lok Handguard, 1:16, w/ SBA5 Brace

Thumper 5-Inch 1:16 .45 ACP AR-45 M-LOK Pistol Full Build Kit with SB Tactical SBA5 Brace

The Thumper Full Build Kit is built around a 5-inch .45 ACP direct blowback barrel with a Vertex Enhanced pistol-caliber billet upper receiver, a 4.2-inch tubular M-LOK handguard, a complete PCC bolt assembly, charging handle, and SB Tactical SBA5 pistol stabilizing brace. Lower receiver is not included.

Key Features

• 5-inch .45 ACP barrel, slim profile, 4150 CrMoV steel, 1:16 twist, Parkerized finish
• Direct blowback operating system
• Vertex Enhanced pistol-caliber AR-15 billet upper receiver, black, integrated Picatinny top rail
• 4.2-inch tubular M-LOK aluminum handguard, black, 1.77" internal diameter, suppressor-ready
• AR-15 .45 ACP birdcage muzzle brake, Manganese Phosphate finish, with 5/8-inch black crush washer
• PCC AR bolt assembly for .45 ACP and mil-spec quality M4 charging handle included
• Complete mil-spec AR-15 Lower Parts Kit and buffer-system components included
• SB Tactical SBA5 pistol stabilizing brace included
• Lower receiver is not included.

Barrel and Operating System

The 5-inch .45 ACP barrel is machined from 4150 chrome moly vanadium steel in a slim profile with a Parkerized finish and a 1:16 twist. This build runs a direct blowback operating system rather than a gas-driven cycle. The muzzle carries an AR-15 .45 ACP birdcage muzzle brake finished in Manganese Phosphate on 37/64x28 threads, secured with the included 5/8-inch black crush washer.

Upper Receiver and Handguard

The upper receiver is a billet aluminum unit built for the pistol-caliber AR-15 platform, finished in black with an integrated Picatinny top rail. It's paired with a 4.2-inch tubular M-LOK handguard machined from aluminum, finished in black, with a 1.77-inch internal diameter and a suppressor-ready design.

Bolt Assembly and Charging Handle

The kit includes a PCC AR bolt assembly built for .45 ACP, along with a mil-spec quality AR-15 M4 charging handle.

Lower Parts Kit and Buffer System

The kit includes a complete mil-spec AR-15 Lower Parts Kit with an A2-style pistol grip and full fire control group, along with the carbine castle nut and mil-spec receiver end plate. The buffer system pairs an AR-15 9mm carbine buffer with a USA-made standard AR-15 carbine recoil spring, cycling inside a heavy-duty mil-spec AR-15 six-position carbine buffer tube.

Brace

The SB Tactical SBA5 is a multi-position adjustable pistol stabilizing brace built from reinforced polymer in black, with an integrated stabilizing strap. It mounts to the mil-spec carbine receiver extension included in this kit.

Follow all manufacturer instructions and safe handling practices.

Ensure compliance with all applicable federal, state, and local laws.

Lower receiver is not included.