Davidson Defense Mutton Chops 10.5-inch Pistol-Gas 1:8 .338 ARC AR-15 Freefloat Keymod Handguard Pistol Upper Build Kit

Mutton Chops 10.5-inch Pistol-Gas 1:8 .338 ARC AR-15 Freefloat Keymod Pistol Upper Build Kit

The Mutton Chops is a .338 ARC AR-15 Upper Build Kit built around a compact 10.5-inch pistol-length gas platform. The kit centers on a 10.5-inch H-Bar profile 4150 CrMoV steel barrel with a parkerized finish, 1:8 twist rate, and 5/8x24 thread pitch, paired with a GI birdcage flash hider compatible with .308 Winchester, 7.62x39, and .300 Blackout, and a black 5/8-inch crush washer. A micro low-profile steel gas block at 0.750 diameter and a pistol-length gas tube are included on the front end. The 7075-T6 aluminum black anodized upper receiver features M4 feed ramps, a forward assist, and an ejection port door assembly, paired with a 10-inch ultra-slim freefloat KeyMod rail. BCG and charging handle are not included.

Key Features

• 10.5-inch H-Bar profile 4150 CrMoV steel barrel, parkerized finish, 1:8 twist, 5/8x24 thread pitch, .338 ARC
• Pistol-length gas system
• Pistol-length gas tube
• Micro low-profile steel gas block, 0.750
• GI birdcage flash hider, 5/8x24, compatible with .308 Winchester, 7.62x39, and .300 Blackout, black 5/8-inch crush washer included
• 7075-T6 aluminum upper receiver, black anodized, M4 feed ramps, forward assist, ejection port door assembly
• 10-inch ultra-slim freefloat KeyMod rail
• BCG and charging handle not included

Perfect For

• Builders sourcing a .338 ARC AR-15 pistol upper build kit with a 10.5-inch parkerized H-Bar 4150 CrMoV barrel, 7075-T6 black anodized upper receiver with forward assist, and 10-inch ultra-slim freefloat KeyMod rail, pairing it with their own 6.5 Grendel II bolt carrier group and charging handle
• Shooters building a compact 10.5-inch pistol-gas .338 ARC platform who prefer to select their own BCG while having the parkerized H-Bar 4150 CrMoV barrel, black anodized upper receiver with M4 feed ramps and forward assist, and freefloat KeyMod rail covered in one kit
• AR-15 pistol builders who want a .338 ARC upper build kit with a GI birdcage flash hider at 5/8x24 and a 10-inch ultra-slim freefloat KeyMod rail without sourcing components separately

Barrel and Muzzle Device

The 10.5-inch H-Bar profile barrel is chambered in .338 ARC and constructed from 4150 CrMoV steel with a parkerized finish. The twist rate is 1:8 and the thread pitch is 5/8x24, which matches the included GI birdcage flash hider, compatible with .308 Winchester, 7.62x39, and .300 Blackout. A black 5/8-inch crush washer, a micro low-profile steel gas block at 0.750 diameter, and a pistol-length gas tube cover the front end gas configuration on this pistol-length platform.

Upper Receiver and Handguard

The 7075-T6 aluminum upper receiver carries a black anodized finish with M4 feed ramps, a forward assist, and an ejection port door assembly. The 10-inch ultra-slim freefloat KeyMod rail features KeyMod attachment points along the body for accessory mounting. These two components define the exterior structure of the upper assembly on this AR-15 pistol platform.

Follow safe handling and manufacturer instructions. Ensure compliance with all applicable federal, state, and local laws. BCG and charging handle are not included. Verify compatibility with your specific .338 ARC lower receiver and bolt carrier group before use.