Davidson Defense Bjorn 20-inch Rifle-Gas 1:8 6.5 Creedmoor AR-10 M-Lok Rifle Complete Upper Build

Bjorn 20-inch Rifle-Gas 1:8 6.5 Creedmoor AR-10 Complete Upper Build

This complete upper pairs a 20-inch 4150 CrMoV barrel with a rifle-length gas system and freefloat M-Lok handguard. The 1:8 twist rate stabilizes heavier 6.5 Creedmoor ammunition, making this configuration ideal for precision shooting at distance. You get a nitride bolt carrier group, low-profile gas block, and a tanker-style muzzle brake already installed.

Key Features

• 20-inch 4150 CrMoV barrel with straight fluting and parkerized finish
• Rifle-length gas system with stainless steel gas tube
• 1:8 twist rate optimized for 6.5 Creedmoor
• Freefloat 19-inch M-Lok handguard for consistent accuracy
• Low-profile gas block with .936 bore diameter
• Nitride bolt carrier group compatible with .308 Win, 6.5 Creedmoor, and .243 Win
• 7075-T6 upper receiver with black anodized finish
• Tanker-style 3-port muzzle brake with 5/8x24 thread

Perfect For

• Long-range precision shooters building a 6.5 Creedmoor AR-10
• Hunters needing reliable performance at extended distances
• Builders looking for a complete upper requiring only a lower receiver
• Shooters who want a rifle-gas system for reduced recoil impulse

Design Intent

The 20-inch barrel length paired with a rifle-gas system creates a balanced platform that minimizes recoil while maintaining velocity for 6.5 Creedmoor ammunition. The 1:8 twist rate handles the full spectrum of available ammunition weights, from 120-grain varmint loads to 140-grain hunting rounds. Freefloat handguard design eliminates barrel contact, which is critical for precision shooting where consistency matters.

Precision Features

The straight-fluted barrel reduces weight without sacrificing rigidity, and the parkerized finish provides durability. The low-profile gas block integrates seamlessly with the handguard mounting system. Recoil Technologies bolt carrier group is engineered for reliable function across multiple calibers, reducing the need for separate bolt carriers when switching between .308 Win and 6.5 Creedmoor platforms.

Handguard and Mounting

The 19-inch Crown Series handguard offers full M-Lok compatibility for mounting optics, lights, and other accessories. The high-profile design provides ample real estate for tactical setups without adding unnecessary bulk. M-Lok slots run the full length, giving you flexibility in accessory placement.

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