Davidson Defense Atriox 10.5-inch Pistol-Gas 1:8 6.5 Grendel AR-15 Freefloat M-Lok Handguard Pistol Upper Build Kit

Atriox 10.5-Inch 6.5 Grendel AR-15 Pistol Upper Build Kit

This upper build kit combines a 10.5-inch 4150 CrMoV barrel with a freefloat M-Lok handguard, chambered in 6.5 Grendel. The kit includes an anodized 7075-T6 aluminum upper receiver with M4 feed ramps, micro low-profile gas block, pistol-length gas tube, GI birdcage flash hider, and forward assist assembly. BCG and charging handle are not included.

Key Features

• 10.5-inch HBAR barrel, 4150 CrMoV steel with parkerized finish, 1:8 twist rate
• Freefloat M-Lok handguard with quad rail section, 6061-T6 aluminum, black
• Anodized AR-15 upper receiver with M4 feed ramps, 7075-T6 aluminum
• Pistol-length gas system with stainless gas tube and .750 micro low-profile gas block
• 5/8x24 threaded barrel with GI birdcage flash hider
• Forward assist assembly included

Perfect For

• Compact 6.5 Grendel builds requiring pistol-length gas systems
• Shooters prioritizing M-Lok accessory compatibility with quad rail section
• Builders seeking HBAR profile barrels for enhanced rigidity
• Configurations demanding freefloat handguards with modular mounting options

6.5 Grendel Chambering

6.5 Grendel offers extended effective range and superior ballistic performance compared to standard 5.56 NATO, making it well suited for precision applications where barrel length constraints apply.

M-Lok Freefloat Handguard with Quad Rail

The freefloat M-Lok handguard features 6061-T6 aluminum construction with M-Lok slots for modular accessory attachment and an integrated quad rail section for direct Picatinny mounting. The freefloat design isolates the barrel from external pressure, supporting accuracy in compact upper configurations.

Pistol-Length Gas System

This kit uses a pistol-length gas system with a stainless gas tube and .750 micro low-profile gas block positioned beneath the handguard. The pistol-length configuration is optimized for the 10.5-inch barrel length.

Compatibility and Assembly

This upper build kit is compatible with standard AR-15 lower receivers. All components use mil-spec dimensions and threading, including the 5/8x24 TPI muzzle threads matching the included GI birdcage flash hider.

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