Davidson Defense Pipeline w/Gauntlet Arms Brace 7.5-inch 1:16 45ACP AR-45 Freefloat Tubular Handguard Pistol Full Build Kit

Pipeline w/Gauntlet Arms Brace 7.5-inch .45 ACP AR-45 Full Build Kit

The Pipeline w/Gauntlet Arms Brace is a 7.5-inch .45 ACP AR-45 Full Build Kit built around a Bear Creek Arsenal barrel, a 6061 billet pistol-caliber upper receiver, and a Gauntlet Arms polymer pistol stabilizing brace. The kit pairs its upper-side barrel and receiver group with a PCC bolt assembly, Mil-Spec charging handle, complete Lower Parts Kit, and pistol-caliber buffer-system components. The stabilizing brace ships as part of this kit, attached to the pistol buffer tube assembly. The lower receiver is not included, leaving the buyer to select and supply that component separately.

Key Features

• 7.5-inch .45 ACP Bear Creek Arsenal barrel, 1:16 twist
• 6061 billet pistol-caliber AR-15 upper receiver
• 7-inch free-float smooth handguard
• KAK Industry .45 ACP Micro Flash Can muzzle device
• Gauntlet Arms polymer pistol stabilizing brace included
• Complete Mil-Spec Lower Parts Kit and pistol-caliber buffer-system components included
• Lower receiver is not included.

Barrel and Muzzle Device

The Pipeline's barrel is a Bear Creek Arsenal 7.5-inch .45 ACP barrel built from 4150 chrome moly vanadium steel with a Parkerized finish and an M4 contour. It carries a 1:16 twist rate, a .578x28 muzzle thread, and a .750-inch gas block journal, and it operates on a direct blowback system rather than a gas-driven cycle. A KAK Industry Micro Flash Can chambered for .45 ACP is installed at the muzzle using the matching .578x28 thread pattern, secured with the included 5/8-inch black crush washer. Together these components define the barrel group that anchors the rest of the build.

Upper Receiver and Handguard

The upper receiver is a 6061 aluminum billet unit built specifically for pistol-caliber AR-15 platforms, giving the Pipeline its upper-side structural foundation. It's paired with a 7-inch free-float handguard, a smooth tubular design that mounts independent of the barrel for a clean, uninterrupted forend. The handguard and receiver are matched to the barrel's dimensions and thread specifications supplied with this kit. Both components ship as part of the upper-side assembly included in the Full Build Kit.

Bolt Assembly and Charging Handle

A PCC AR bolt assembly built for .45 ACP is included with the kit, matched to the pistol-caliber upper receiver and barrel. A Mil-Spec AR-15 M4 charging handle is included alongside it to complete the upper-side operating components. Both parts are sized and configured for this .45 ACP pistol-caliber build rather than a standard 5.56 or .223 configuration. Together they round out the components needed to complete the upper assembly.

Lower Parts Kit and Buffer System

The Pipeline includes a complete Mil-Spec AR-15 Lower Parts Kit, giving the buyer the fire-control and lower-control components needed once a lower receiver is supplied. The buffer system consists of a heavy-duty pistol buffer tube built for AR-15 and AR-style pistols, an 8-ounce pistol-caliber carbine buffer finished in black, a standard USA-made AR-15 carbine recoil spring, a standard AR-15 carbine castle nut, and a Mil-Spec AR-15/M16 receiver end plate. These components are sized for the pistol-caliber buffer configuration used in this build rather than a standard rifle-length setup. All of these lower-side parts are included with the kit, while the lower receiver itself remains excluded.

Stabilizing Brace

The Pipeline w/Gauntlet Arms Brace includes a Gauntlet Arms polymer pistol stabilizing brace finished in black. The brace is supplied as part of this kit's furniture, mounted on the pistol buffer tube assembly rather than left to the buyer to source separately. It's built specifically for pistol-configured AR platforms like this .45 ACP build. Its inclusion rounds out the buffer-system components covered elsewhere 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.