Davidson Defense Mutton Chops w/Magpul BTR Brace 10.5-inch Pistol-Gas 1:8 .338 ARC AR-15 Freefloat Keymod Handguard Pistol Full Build Kit

Mutton Chops Magpul BTR Brace 10.5-inch Pistol-Gas 1:8 .338 ARC AR-15 Freefloat Keymod Pistol Full Build Kit

The Mutton Chops is a .338 ARC AR-15 Full 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, paired with a 10-inch ultra-slim freefloat KeyMod rail. A complete AR-15 6.5 Grendel II bolt carrier group with QPQ nitride finish and a Mil-Spec AR-15 M4 charging handle complete the upper side. The lower hardware includes a complete Mil-Spec AR-15 lower parts kit, a Mil-Spec heavy-duty 6-position aluminum carbine buffer tube, a standard 3 oz carbine buffer, a USA-made standard carbine recoil spring, a Mil-Spec AR-15 M16 end plate, and a Mil-Spec AR-15 castle nut. The Magpul BTR pistol brace in black is included. Lower receiver 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
• 10-inch ultra-slim freefloat KeyMod rail
• Complete AR-15 6.5 Grendel II bolt carrier group, QPQ nitride finish
• Mil-Spec AR-15 M4 charging handle
• Complete Mil-Spec AR-15 lower parts kit
• Mil-Spec heavy-duty 6-position aluminum carbine buffer tube
• Standard carbine buffer, 3 oz
• Standard carbine recoil spring, made in USA
• Mil-Spec AR-15 M16 end plate
• Mil-Spec AR-15 castle nut
• Magpul BTR pistol brace, black

Perfect For

• Builders sourcing a complete .338 ARC AR-15 pistol full build kit with a 10.5-inch parkerized H-Bar 4150 CrMoV barrel, 7075-T6 black anodized upper receiver, 6.5 Grendel II QPQ nitride BCG, 10-inch ultra-slim freefloat KeyMod rail, and Magpul BTR brace on a Mil-Spec carbine buffer tube already included, pairing it with their own lower receiver
• Shooters building a compact 10.5-inch pistol-gas .338 ARC platform who want the 6.5 Grendel II BCG, charging handle, complete lower parts kit, and Magpul BTR brace covered in one kit with a freefloat KeyMod rail
• AR-15 pistol builders who want a .338 ARC full build kit with a 6.5 Grendel II QPQ nitride BCG and a Magpul BTR brace 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. 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.

Bolt Carrier Group and Charging Handle

The complete AR-15 6.5 Grendel II bolt carrier group carries a QPQ nitride finish and is compatible with the .338 ARC platform. A Mil-Spec AR-15 M4 charging handle is included to complete the upper component set.

Lower Parts Kit and Buffer System

The complete Mil-Spec AR-15 lower parts kit covers the internal lower receiver components. The buffer system includes a Mil-Spec heavy-duty 6-position aluminum carbine buffer tube, a standard 3 oz carbine buffer, a USA-made standard carbine recoil spring, a Mil-Spec AR-15 M16 end plate, and a Mil-Spec AR-15 castle nut. The Magpul BTR pistol brace in black pairs with the included Mil-Spec carbine buffer tube and covers the rear brace interface for this pistol lower build kit.

Follow safe handling and manufacturer instructions. Ensure compliance with all applicable federal, state, and local laws. Lower receiver not included. Verify local and state laws regarding pistol brace use and classification. Verify compatibility with your specific .338 ARC lower receiver before use.