SKU CSSI|CA34B8D0FAB Category

CMMG Banshee Mk4 AR-15 Upper Group .338 ARC 10.5″ Barrel Black

CMMG Banshee Mk4 AR-15 Upper Group .338 ARC 10.5″ Barrel Black

$843.00

1 in stock

Made to combine the prowess of the AR15 platform with the stopping power of a large bore caliber 338 ARC strives to emulate the sub or supersonic versatility of the now ubiquitous 300 BLK cartridge with more energy on target and less gas system tuning when switching from suppressed to unsuppressed. 

To maximize parts compatibility 338 ARC utilizes the same bolt as 6.5 Grendel AR15s. For those that like to load their own ammo CMMG 338 ARC barrels feature a slower 1:8 twist rate to allow the use of more traditional construction .338 caliber projectiles. Pistol options include DISSENT models with 6.5" 10.5" and 16.1" barrel lengths and BANSHEE models with 10.5" barrels. 

  • Platform: Mk4
  • Caliber: .338 ARC
  • Operating System: Compact Action-Direct Impingement
  • Barrel Length: 10.5
  • Barrel Twist: 1:8
  • Barrel Contour: MT
  • Barrel Material :4140CM Nitride Finish
  • Barrel Twist: 1:8
  • Muzzle Device: CMMG ZEROED Linear Compensator
  • Muzzle Thread: 5/8 x 24
  • Gas Block: Non-Adjustable 0.750"
  • Upper Receiver: Mk4 Billet 6061 T6 Aluminum
  • Hand Guard: EML9
  • Finish: Cerakote
  • Charging Handle: Dissent Side Charger
  • Weight: 3.1 lbs

Additional information

Upc

840442506247

Manufacturer

CMMG

Manufacturer part number

34B8D0F-AB

Shipping weight

4.007

FAQ

BJ Firearms LLC is a federally licensed firearms business focused on providing quality firearms, accessories, and related services while promoting responsible ownership, education, and community engagement.

The company was founded to serve firearm enthusiasts with knowledgeable service, real-world experience, and a commitment to professionalism and safety.

We focus on real experience, personalized service, hands-on product knowledge, and community involvement — not just sales. Our goal is to help customers make informed decisions and feel confident with their equipment.

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We work with everyone — from first-time buyers to experienced enthusiasts. Education and guidance are a big part of what we do.

We offer firearms, accessories, gear, and related equipment depending on availability and customer needs.

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