CM15 6MM ARC 18″ AR15 Rifle – FDE Metallic

CM15 6mm ARC DMR — 18-Inch FDE Metallic

The 6mm ARC DMR from Chattahoochee Munitions combines the CM15 semi-automatic AR15 platform with an 18-inch barrel and rifle-length gas system. This FDE Metallic configuration is part of Overwatch 6, CM’s supersonic precision and predator-hunting family.

The complete firearm includes billet-aluminum receivers, a TriggerTech AR15 Duty trigger, Superlative Arms adjustable gas block, Odin adjustable buffer and CM15 low-mass bolt carrier group. Coyote B5 Systems furniture and a Coyote DURAMAG complement the FDE Metallic finish.

6mm ARC DMR Applications

DMR stands for designated marksman rifle and describes an application rather than a guaranteed accuracy level. This CM15 configuration offers semi-automatic operation, an 18-inch barrel and accessory interfaces for compatible optics and support equipment.

The complete precision system also depends on ammunition, optics, shooting position and shooter capability. Confirm ammunition performance in the individual firearm rather than assigning an effective distance from the cartridge name alone.

18-Inch CM15 Barrel

This 6mm ARC DMR uses an 18-inch straight-fluted 416R stainless steel barrel with a black Cerakote exterior finish.

Specifications include a 1:7 twist, shouldered crown, 5/8×24 muzzle threads and a .750-inch gas journal. The 18-inch configuration uses a rifle-length gas system.

Rifle-Length Gas and Adjustable Components

The rifle includes a rifle-length Melonite-finished gas tube and a Superlative Arms .750-inch adjustable gas block with DLC Coyote finish. An Odin adjustable AR15 buffer is also standard.

These components form part of the complete CM15 operating system. Rifle-length gas distinguishes this configuration from CM’s mid-length 16-inch offerings.

TriggerTech AR15 Duty Trigger

The 6mm ARC DMR includes your choice of TriggerTech AR15 Duty trigger: straight, curved or two-stage straight. Each option has a 3.5 lb total pull weight.

Select the trigger profile and stage configuration that suit your preference. Product photographs may depict older triggers; current supplied options are the TriggerTech Duty selections listed here.

FDE Metallic Billet Receivers

The CM15 upper and lower receivers are CNC-machined from 7075-T6 billet aluminum and finished in FDE Metallic Cerakote. The lower incorporates an integral trigger guard, a machined magazine well with a wide flare and fire/safe pictograms on both sides.

The receiver set uses AR15-pattern dimensions. The lower receiver’s listed component weight is 8.0 oz; complete firearm weight is provided separately below.

Ambidextrous Controls and Charging Handle

This 6mm ARC DMR includes CM ambidextrous safety, magazine-release and bolt-release controls. CM15 pivot and takedown pins complete the principal lower-receiver hardware.

The CM15 ambidextrous charging handle uses 7075 aluminum and is produced through the Warhammer collaboration with Breek Arms. A CM15 dust cover and forward assist complete the upper-receiver equipment.

CM15 Low-Mass Bolt Carrier Group

The CM15 low-mass bolt carrier group uses a 9310 steel bolt with high-pressure testing and magnetic-particle inspection. The bolt, carrier and gas key have nitride finishes.

The carrier incorporates lightening cuts. The assembly also includes a tool-steel extractor, hardened gas key and staked Grade 8 fasteners.

15-Inch CM15 LWS Handguard

The 6mm ARC DMR uses a 15-inch CM15 LWS handguard finished in FDE Metallic Cerakote. Its 6061-aluminum construction incorporates a dual-taper attachment system and steel barrel nut.

The handguard provides M-LOK interfaces on the sides and bottom, a full Picatinny top rail and QD sling attachment points at the 3 and 9 o’clock positions. Coyote B5 Systems rail covers are included.

Coyote Furniture and Dimensions

A Coyote B5 Systems Bravo stock and grip complete the furniture configuration. The CM buffer tube is finished in FDE Metallic Cerakote and includes a QD endplate.

Overall length adjusts from 35.50 to 38.75 inches, while length of pull adjusts from 11.00 to 14.25 inches. Weight is 6 lb 12 oz with an unloaded magazine and no accessories.

Included Coyote DURAMAG

One Coyote 10-round DURAMAG is included with this 6mm ARC DMR. This is the AR15-pattern magazine CM has vetted for its CM15 6mm ARC firearms.

For additional magazines, visit the 6mm ARC AR15 magazine page. The CM15 does not use the AICS-pattern magazine supplied for the bolt-action CM7S.

Muzzle-Device Options

Product photographs depict a Yankee Hill three-port brake. Available alternatives include an A2 birdcage, Dead Air KeyMo, SilencerCo ASR or Rugged three-port brake.

Contact Chattahoochee Munitions to confirm the selected muzzle device and any price adjustment for an alternative. A suppressor mount must match the selected suppressor’s mounting system.

Suppressor Preference for the CM15

Chattahoochee Munitions prefers a flow-through or low-backpressure suppressor for this 6mm ARC DMR. That preference reflects the gas-operated CM15 platform and its supersonic application.

Confirm cartridge approval, bore suitability, barrel-length rating and mounting compatibility. Supersonic ammunition continues to produce a sonic crack when suppressed.

Read our 6mm ARC suppressor guide for CM’s different preferences for semi-automatic and bolt-action firearms.

6mm ARC DMR Specifications

• Manufacturer: Chattahoochee Munitions
• Platform: CM15, AR15-pattern semi-automatic
• Caliber: 6mm ARC
• Barrel length: 18 inches
• Barrel material: 416R stainless steel
• Barrel profile feature: Straight fluting
• Barrel finish: Black Cerakote
• Twist rate: 1:7
• Crown: Shouldered
• Muzzle threads: 5/8×24
• Gas journal: .750 inch
• Gas system: Rifle-length
• Gas tube: Melonite finish
• Gas block: Superlative Arms adjustable, DLC Coyote finish
• Buffer: Odin adjustable AR15 buffer
• Receivers: CNC-machined 7075-T6 billet aluminum
• Receiver finish: FDE Metallic Cerakote
• Trigger guard: Integral
• Magazine well: Machined with wide flare
• Controls: CM ambidextrous safety, magazine release and bolt release
• Trigger: TriggerTech AR15 Duty
• Trigger options: Straight, curved or two-stage straight
• Trigger pull: 3.5 lb total
• Bolt carrier group: CM15 low-mass
• Bolt material: 9310 steel
• Bolt testing: High-pressure tested and magnetic-particle inspected
• Bolt, carrier and gas-key finish: Nitride
• Extractor: Tool steel
• Charging handle: CM15 ambidextrous, 7075 aluminum, Breek Arms collaboration
• Handguard: CM15 LWS, 15 inches, 6061 aluminum
• Handguard finish: FDE Metallic Cerakote
• Handguard mounting: Dual-taper attachment with steel barrel nut
• Accessory interfaces: M-LOK sides and bottom; full Picatinny top rail
• Handguard sling interfaces: QD at 3 and 9 o’clock
• Stock: B5 Systems Bravo, Coyote
• Grip: B5 Systems, Coyote
• Rail covers: B5 Systems, Coyote
• Buffer tube: CM mil-spec, FDE Metallic Cerakote
• Endplate: QD
• Magazine: One Coyote 10-round DURAMAG
• Weight: 6 lb 12 oz with unloaded magazine and no accessories
• Overall length: 35.50–38.75 inches
• Length of pull: 11.00–14.25 inches

Measurement clarification: These are firearm measurements. Weight and dimensions shown in the shipping information tab are for shipping purposes.

Limited Lifetime Warranty

This firearm carries Chattahoochee Munitions’ limited lifetime warranty for the original purchaser, subject to the published warranty terms, original-configuration requirements and exclusions.

Explore Overwatch 6

Compare this 6mm ARC DMR with other CM15 configurations and the CM7S bolt-action family at Overwatch 6.

For cartridge background and platform comparisons, visit our 6mm ARC rifle guide.