CM15 338 ARC 8.5″ 1:5 Twist Upper with Options

CM15 338 ARC 8.5″ Upper

• CM 6061 lightweight billet aluminum receiver
  • Reliefs featured throughout the receiver
  • Picatinny rail milled channel for a sleek/light weight option
• CM 6061 7.25″ MLOK handguard
  • QD Sockets at 3 and 9 o’clock
  • Full Picatinny top rail
• Choice of Suppressor Host Muzzle Device or Thread Protector
• CM15 Low Mass Bolt Carrier Group
  • 9310 Hardened Steel Bolt
  • 17-4 Stainless Steel Firing Pin
  • 8620 Carrier and Key
  • MPI Tested
  • Hardened Extractor S7 Steel
• CM15 Warhammer Ambidextrous Charging Handle – in collaboration with Breek Arms
• Superlative Arms Adjustable Gas Block
• CM Melonite Gas Tube
• CM15 338 ARC 8.5″ Barrel
  • 416R Stainless Steel
  • Medium Profile
  • QPQ Corrosion Resistant
  • 1:5 Twist
  • Pistol Gas
  • .750 Gas Journal
  • 5/8×24 threaded muzzle

CM15 338 ARC 8.5″ Upper: The Ultimate Compact Thumper

The CM15 338 ARC 8.5″ Upper is the pinnacle of Personal Defense Weapon (PDW) engineering. By chambering the revolutionary 338 Advanced Rifle Cartridge in an 8.5-inch barrel, we’ve created a system that delivers massive frontal diameter and heavy-hitting energy in a package that is exceptionally easy to stow and maneuver.

Optimized 1:5 Twist Stability

To master the heavy, high-BC projectiles that make the 338 ARC famous, rotation is key. Our ultra-fast 1:5 twist rate is purpose-built to stabilize heavy subsonic rounds in a short bore. This ensures your projectiles maintain a true flight path and deliver maximum terminal energy upon impact, eliminating the stability issues common in slower-twist short barrels.

Versatile and Duty-Ready

The 8.5-inch length is the “sweet spot” for suppressed use, keeping the overall footprint compact even with a silencer attached. With our customizable options, you can tailor this upper with your choice of M-LOK handguards, specialized bolt carrier groups, and charging handles to meet your specific mission requirements.

Key Features:

• 8.5” 4150 CMV Barrel: Maximum maneuverability with professional-grade durability.

• 1:5 Twist Rate: Specifically tuned for heavy .338 caliber stability.

• Big-Bore Reliability: Enlarged ejection port for flawless cycling of 338 ARC brass.

The CM15 8.5″ 338 ARC Upper is the definitive choice for shooters who need maximum impact in a minimum profile.