Davidson Defense Harbinger w/Gauntlet Arms Brace 11.5-inch Carbine-Gas 1:8 .223 Wylde AR-15 Freefloat Tubular M-Lok Handguard Pistol Full Build Kit

Davidson Defense Harbinger with Gauntlet Arms Brace 11.5-Inch Carbine-Gas 1-in-8 .223 Wylde AR-15 Freefloat Tubular M-LOK Pistol Full Build Kit

The Davidson Defense Harbinger Full Build Kit is a .223 Wylde AR-15 pistol configuration built around an 11.5-inch government profile barrel with a 1-in-8 twist rate and a carbine-length gas system. The kit includes a 5.56 nitride bolt carrier group, AR-15 M4 mil-spec charging handle, Gauntlet Arms polymer stabilizing brace, lower parts kit, aluminum buffer tube, 3 oz standard carbine buffer, AR-15 carbine recoil spring, end plate, and castle nut. The lower receiver is not included.

Key Features

• 11.5-inch government profile .223 Wylde barrel, 4140 CrMoV steel, nitride finish, 1-in-8 twist, carbine-length gas system, 1-in-2x28 thread pitch
• 12.5-inch tubular M-LOK freefloat handguard, aluminum
• Stripped AR-15 upper receiver, M4 feed ramps, 7075 T6 aluminum, anodized finish
• 5.56 nitride bolt carrier group, 9310 alloy steel bolt head, 8620 alloy steel body, nitride finish
• AR-15 M4 mil-spec charging handle, anodized, black
• Micro low-profile gas block, 0.750 barrel diameter compatible
• Gauntlet Arms polymer stabilizing brace, black
• Steel flash can muzzle device, 1-in-2x28 thread pitch
• Aluminum buffer tube
• Standard carbine buffer, 3 oz
• AR-15 carbine recoil spring, spring steel
• Lower receiver not included

Perfect For

• AR-15 pistol builders seeking a compact .223 Wylde configuration
• Gunsmiths sourcing a complete kit with a Gauntlet Arms brace
• Builders prioritizing a carbine-length gas system in an 11.5-inch barrel
• Enthusiasts selecting a tubular M-LOK handguard platform for their pistol build

Barrel and Upper Receiver

The 11.5-inch government profile barrel is made from 4140 CrMoV steel with a nitride finish and a 1-in-8 twist rate. The barrel is threaded at 1-in-2x28 and uses a carbine-length gas system with an included micro low-profile gas block compatible with 0.750 barrel diameters. The stripped AR-15 upper receiver features M4 feed ramps and is constructed from 7075 T6 aluminum with an anodized finish.

12.5-Inch Tubular M-LOK Freefloat Handguard

The 12.5-inch tubular M-LOK freefloat handguard is constructed from aluminum and provides M-LOK interface slots along its exterior for accessory attachment. At 12.5 inches, the handguard extends past the 11.5-inch barrel, meaning the barrel does not protrude past the handguard. The included muzzle device provides the length needed to clear the handguard profile.

5.56 Bolt Carrier Group and Charging Handle

The 5.56 nitride bolt carrier group features a 9310 alloy steel bolt head and an 8620 alloy steel body, both with a nitride finish. This bolt carrier group is compatible with .223 Wylde, 5.56 NATO, .300 Blackout, and .350 Legend configurations. The AR-15 M4 mil-spec charging handle is anodized black and is included as part of the upper operating components in this kit.

Gauntlet Arms Stabilizing Brace and Buffer System

The Gauntlet Arms polymer stabilizing brace is black and is included as part of this full build kit. The buffer system consists of an aluminum buffer tube, a 3 oz standard carbine buffer, and an AR-15 carbine recoil spring made from spring steel. End plate and castle nut are included as canonical full build kit components.

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