Davidson Defense Harbinger w/SBA3 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 SB Tactical SBA3 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, SB Tactical SBA3 adjustable pistol stabilizing brace, lower parts kit, mil-spec buffer tube, 3 oz standard carbine buffer, standard AR-15 carbine recoil spring, AR-15 M16 mil-spec receiver end plate, and AR-15 carbine castle nut. The lower receiver is not included.

Key Features

• 11.5-inch government profile .223 Wylde barrel, 4140 CrMV steel, nitride finish, 1-in-8 twist, carbine-length gas system, 1-in-2x28 thread pitch
• Tubular M-LOK freefloat handguard, aluminum
• AR-15 upper receiver, M4 feed ramps, 7075 T6 aluminum, anodized finish
• 5.56 nitride bolt carrier group, 9310 alloy steel, nitride finish
• AR-15 M4 mil-spec charging handle
• Micro low-profile gas block, 0.750 barrel diameter compatible
• SB Tactical SBA3 adjustable pistol stabilizing brace
• Steel flash can muzzle device, 1-in-2x28 thread pitch
• Standard carbine buffer, 3 oz
• Standard AR-15 carbine recoil spring
• AR-15 M16 mil-spec receiver end plate
• AR-15 carbine castle nut
• Lower receiver not included

Perfect For

• AR-15 pistol builders seeking a compact .223 Wylde configuration
• Gunsmiths sourcing a complete kit with the SB Tactical SBA3 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 CrMV 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 AR-15 upper receiver features M4 feed ramps and is constructed from 7075 T6 aluminum with an anodized finish.

Tubular M-LOK Freefloat Handguard

The tubular M-LOK freefloat handguard is constructed from aluminum and provides M-LOK interface slots along its exterior for accessory attachment. No handguard length was provided in the spec sheet, so dimensional details and barrel-to-handguard relationship are omitted here.

5.56 Bolt Carrier Group and Charging Handle

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

SB Tactical SBA3 Adjustable Pistol Stabilizing Brace and Buffer System

The SB Tactical SBA3 adjustable pistol stabilizing brace is included as part of this full build kit. The buffer system consists of a mil-spec buffer tube, a 3 oz standard carbine buffer, a standard AR-15 carbine recoil spring, an AR-15 M16 mil-spec receiver end plate, and an AR-15 carbine castle nut.

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