Davidson Defense Atriox 16-inch Carbine-Gas 1:8 338 ARC AR-15 M-Lok Handguard Rifle Upper Build Kit

Atriox 16-inch Carbine-Gas 1:8 .338 ARC AR-15 M-LOK Upper Build Kit

The Atriox is a .338 ARC AR-15 Upper Build Kit built around a 16-inch carbine-length gas platform. The kit centers on a 16-inch HBAR profile barrel in 4150 CrMoV steel with a phosphate finish, 1:8 twist rate, and 5/8x24 thread pitch, paired with a GI birdcage flash hider at 5/8x24 and a black 5/8-inch crush washer. A micro low-profile gas block at 0.750 diameter and a carbine-length stainless steel gas tube are included on the front end. The 7075-T6 aluminum upper receiver carries an anodized finish with M4 feed ramps, a forward assist assembly, and an ejection port door, rod, and spring, paired with a 15-inch freefloat M-LOK handguard in 6061-T6 aluminum. BCG and charging handle are not included.

Key Features

• 16-inch HBAR profile barrel, 4150 CrMoV steel, phosphate finish, 1:8 twist, 5/8x24 thread pitch, .338 ARC
• Carbine-length gas system
• Carbine-length stainless steel gas tube
• Micro low-profile gas block, 0.750
• GI birdcage flash hider, 5/8x24, black 5/8-inch crush washer included
• 7075-T6 aluminum upper receiver, anodized, M4 feed ramps, forward assist assembly, ejection port door, rod, and spring
• 15-inch freefloat M-LOK handguard, 6061-T6 aluminum
• BCG and charging handle not included

Perfect For

• Builders sourcing a complete .338 ARC AR-15 upper build kit with a 4150 CrMoV HBAR barrel and 15-inch freefloat M-LOK handguard, pairing it with their own bolt carrier group and charging handle
• Shooters building a 16-inch .338 ARC carbine-gas platform who prefer to select their own BCG while having the HBAR barrel, carbine-length stainless gas tube, and forward assist upper receiver covered in one kit
• AR-15 builders who want a .338 ARC upper build kit with a forward assist assembly, ejection port door with rod and spring, and GI birdcage flash hider at 5/8x24 without sourcing components separately

Barrel and Muzzle Device

The 16-inch HBAR profile barrel is chambered in .338 ARC and constructed from 4150 CrMoV steel with a phosphate finish. The twist rate is 1:8 and the thread pitch is 5/8x24, which matches the included GI birdcage flash hider. A black 5/8-inch crush washer, a micro low-profile gas block at 0.750 diameter, and a carbine-length stainless steel gas tube cover the front end gas configuration on this carbine-length platform.

Upper Receiver and Handguard

The 7075-T6 aluminum upper receiver carries an anodized finish with M4 feed ramps, a forward assist assembly, and an ejection port door, rod, and spring. The 15-inch freefloat M-LOK handguard is 6061-T6 aluminum with M-LOK attachment points along the body for accessory mounting. These two components define the exterior structure of the upper assembly on this .338 ARC platform.

Follow safe handling and manufacturer instructions. Ensure compliance with all applicable federal, state, and local laws. BCG and charging handle are not included.