CM7S 8.6 Blackout 12″ Lightweight and Compact Bolt Action Pistol or SBR – Cobalt Kinetics Green

8.6 Blackout Short Barreled Rifle | CM7S 12″ CKG

NFA ITEM: When configured with the shoulder stock, this firearm is an NFA-regulated short-barreled rifle (SBR) and must be transferred in accordance with applicable federal, state and local requirements. A pistol configuration with a Tailhook brace is also available.

The CM7S 8.6 Blackout Short Barreled Rifle combines the Chattahoochee Munitions CM7S bolt action with a compact 12-inch barrel, billet CM7 chassis, TriggerTech Primary trigger and vetted AICS-pattern magazine system. This Cobalt Kinetics Green and Coyote configuration is built around the same CM7S architecture used in our full-length rifles while substantially reducing overall length.

The 12-inch barrel places this CM7S near the barrel length that has proven particularly useful during our development and testing of 8.6 Blackout. In the subsonic loads we have evaluated, powder utilization is effectively complete at approximately 12 to 12.5 inches.

CM also offers a choice of 1:3 or 1:5 twist, allowing the firearm to be configured around the intended projectile and ammunition rather than treating one twist rate as universally correct for every 8.6 BLK application.

CM7S Bolt Action

At the center of this 8.6 Blackout Short Barreled Rifle is the Chattahoochee Munitions CM7S action. The CM7S uses a Remington 700 footprint with a three-lug bolt and 60-degree throw in a purpose-built action used throughout our bolt-action firearm family.

• Remington 700 footprint
• Three-lug bolt design
• 60-degree bolt throw
• M16-style extractor
• One-piece .718″ bolt body
• Wire EDM raceways
• Pinned 20 MOA Picatinny rail
• Large ejection port
• Lightweight action-body cutout
• .062″ firing pin
• Integrated .300″ recoil lug
• Tool-less fire-control removal
• Accepts Remington 700-style triggers
• 1-1/16″-16 barrel thread
• Side bolt-stop release
• Oversized bolt knob
• Spiral-fluted bolt
• Full PVD coating
• Action weight: 25 oz

The three-lug geometry provides a short 60-degree bolt lift, complementing the compact dimensions of the 12-inch firearm while retaining the same action architecture as the larger CM7S configurations.

12″ Mos-Tek 8.6 Blackout Barrel

The CM7S uses a 12-inch Mos-Tek premium bolt-action barrel manufactured from 416R stainless steel with 5R rifling. Customers can select either a 1:3 or 1:5 twist based on the intended projectile and ammunition.

• 12″ barrel length
• 416R stainless steel
• 5R rifling
• Choice of 1:3 or 1:5 twist
• Shouldered crown
• 5/8×24 muzzle threads
• Remage barrel-nut mounting system
• E100 Blackout Cerakote

CM offers both twist rates because projectile selection matters. In our testing around this barrel-length range, 1:5 twist has generally performed well with projectiles around 300 grains or less, while 1:3 twist has generally been better suited to heavy subsonic projectiles around 323 grains and above. Projectile construction, length, ammunition and velocity can also influence stabilization.

For a deeper discussion of CM testing with barrel length, projectile weight, twist rate and suppression, see our 8.6 Blackout Subsonic Guide.

TriggerTech Remington 700 Primary Trigger

The CM7S 8.6 Blackout Short Barreled Rifle is equipped with a TriggerTech Remington 700 Primary trigger, available with either a flat or curved trigger.

The Primary provides an adjustable pull-weight range of approximately 1.5 to 4.0 pounds. The CM7S action also accepts compatible Remington 700-style triggers for customers who may choose another trigger configuration later.

CM7 Billet Chassis

The Cobalt Kinetics Green CM7 chassis is machined from billet aluminum and provides a compact, modular foundation for the CM7S. It uses an AICS-pattern magazine system and incorporates the adjustment and accessory provisions needed for a configurable bolt-action firearm.

• Flared AICS-pattern magazine well
• Ambidextrous magazine release
• Large trigger guard for gloved operation
• Machined billet-aluminum construction
• Modular rear adapter system
• M-LOK compatible
• Dual integrated QD sling sockets
• Compatible with AR-15 pistol grips without integrated dovetails

SBR and Pistol Configurations

The primary configuration of this product is the 8.6 Blackout Short Barreled Rifle. The SBR uses a telescoping shoulder stock with an adjustable cheek riser, providing a compact package with adjustable length of pull.

A pistol configuration is also available with a telescoping Tailhook brace instead of the shoulder stock. The appropriate configuration can be selected when ordering.

Customers selecting the SBR configuration are purchasing an NFA-regulated firearm. Transfer and possession are subject to applicable federal, state and local requirements.

Vetted AICS Magazine System

Magazine compatibility is part of the complete CM7S system. The action and chassis use an AICS-pattern magazine architecture, and CM uses a vetted magazine configuration with its bolt-action 8.6 Blackout firearms rather than leaving magazine selection to customer experimentation.

Additional CM 8.6 Blackout Magazines are available for the platform.

Compact 8.6 Blackout Short Barreled Rifle

The compact dimensions of an 8.6 Blackout Short Barreled Rifle become particularly useful when a suppressor is added to the firearm. The 12-inch barrel substantially reduces the overall dimensions of the CM7S compared with a conventional 16-inch rifle, helping offset the additional length of the suppressor as part of the complete system.

A bolt action also eliminates the gas-system and buffer-system variables associated with cycling a semi-automatic firearm. Appropriate subsonic and supersonic ammunition can therefore be selected without having to tune a semi-automatic operating system around the load.

The 5/8×24 threaded muzzle provides compatibility with appropriately configured muzzle devices and suppressor mounting systems. Suppressor compatibility should always be confirmed for the specific suppressor, ammunition and firearm configuration.

Why 12 Inches for 8.6 Blackout?

Choosing the barrel length for an 8.6 Blackout Short Barreled Rifle should involve more than simply making the firearm shorter. Barrel length, intended ammunition, projectile weight, twist rate and suppression should be considered together when configuring the complete firearm.

Based on the subsonic loads CM has evaluated, powder utilization is effectively complete at approximately 12 to 12.5 inches. That experience is one reason the 12-inch CM7S occupies an important position between our full-length rifles and our shortest 8.6 Blackout configurations.

The result is a compact firearm that retains enough barrel length to make effective use of the cartridge configurations we have tested while reducing the overall package length for suppressed applications.

Built Around the Intended Ammunition

CM has been building 8.6 Blackout firearms since the cartridge’s early introduction, before SAAMI standardization. Our approach is to configure the firearm around the customer’s intended projectile, ammunition and use rather than treating chambering alone as a complete system.

That is why the CM7S is available with both 1:3 and 1:5 twist barrels and why we provide a vetted magazine solution. Barrel length, twist rate, projectile selection, magazine compatibility and suppression all influence the finished configuration.

For customers specifically looking for a compact bolt-action 8.6 BLK platform, this 8.6 Blackout Short Barreled Rifle combines the CM7S action, 12-inch barrel and adjustable chassis in a purpose-built short configuration.

To compare this compact CM7S with our 16-inch rifles, other short CM7S configurations, CM10 AR10 platforms and supporting components, visit Area 8.6.

CM7S 8.6 Blackout Short Barreled Rifle Specifications

Platform	CM7S Bolt Action
Caliber	8.6 Blackout
Available Configurations	SBR or Pistol
Barrel Length	12″
Barrel Manufacturer	Mos-Tek
Barrel Material	416R Stainless Steel
Rifling	5R
Twist Rate	1:3 or 1:5
Muzzle Threads	5/8×24
Trigger	TriggerTech Remington 700 Primary
Magazine Pattern	AICS
Chassis Finish	Cobalt Kinetics Green Cerakote
Furniture	Coyote
Weight	6 lb 6 oz
Overall Length	23.875″ – 31.00″
Length of Pull	6.0″ – 13.5″

8.6 Blackout Short Barreled Rifle FAQ

Is the CM7S 12″ an SBR?

When ordered with the shoulder stock, yes. The 12-inch CM7S is configured as an 8.6 Blackout Short Barreled Rifle and is an NFA-regulated firearm. It must be transferred and possessed in accordance with applicable federal, state and local requirements.

Can I order this CM7S as a pistol instead?

Yes. A pistol configuration is available using a telescoping Tailhook brace instead of the shoulder stock. Select the appropriate configuration when ordering.

Why does CM offer both 1:3 and 1:5 twist?

CM offers both because the appropriate twist depends on the intended projectile and ammunition. Our testing has generally favored 1:5 for projectiles around 300 grains or less and 1:3 for heavy subsonic projectiles around 323 grains and above in this approximate barrel-length range. Projectile construction, length, ammunition and velocity also matter.

Can the 12″ CM7S be suppressed?

Yes. The barrel uses 5/8×24 muzzle threads for compatible muzzle devices and suppressor mounting systems. Compatibility should always be verified for the suppressor, ammunition and firearm configuration being used.

What magazine does the CM7S use?

The CM7S uses an AICS-pattern magazine architecture. CM offers a vetted 8.6 Blackout Magazine for the bolt-action platform.

Where can I compare other 8.6 Blackout configurations?

Visit Area 8.6 to compare CM7S bolt actions, CM10 AR10 platforms, compact configurations, barreled actions and supporting components.

NFA NOTICE: The shoulder-stock/SBR configuration is an NFA-regulated firearm and is subject to applicable federal, state and local requirements.