CM7S 308 Barreled Action 16″ 1:8 Twist – Rem 700 Short Action

Chattahoochee Munitions manufactures the CM7S 308 Barreled Action, a 16-inch 1:8 twist 308 Winchester barreled action for Remington 700 short-action chassis and stocks.

CM7S 308 Barreled Action

The CM7S 308 Barreled Action combines CM’s Remington 700 short-action footprint with a 16-inch Mos-Tek barrel and versatile 1:8 twist. The barrel is installed, headspaced and ready for a compatible Remington 700 short-action chassis or stock.

This is the same action and barrel specification used in CM’s complete 16-inch CM7S rifles. It is offered separately for customers who want to select their own chassis or stock, trigger, bottom metal, magazine and optic.

The 1:8 twist is intended primarily for conventional supersonic 308 Winchester ammunition across common hunting and target projectile weights of 147 grains and heavier; CM does not recommend lighter bullets in the 1:8. It can also stabilize appropriate subsonic projectiles weighing 220 grains or less.

A trigger, chassis or stock, bottom metal and magazine are not included. The CM7S accepts compatible Remington 700-pattern triggers and fits Remington 700 short-action inlets that accommodate its integrated .300-inch recoil lug.

Explore CM’s complete family of 308 Winchester firearms, ammunition, magazines and technical guides in District 308.

What Is Included

• CM7S short action with bolt
• Full PVD coating on the action and bolt
• Pinned 20-MOA Picatinny optic rail
• Integrated .300-inch recoil lug
• 16-inch Mos-Tek 416R stainless steel barrel
• 1:8 twist with 5R rifling
• Installed and headspaced barrel
• Remage barrel nut
• 5/8×24 muzzle threads
• Thread protector

Not Included

• Trigger
• Chassis or stock
• Bottom metal
• Magazine
• Suppressor or suppressor mount
• Optic or optic rings

CM7S Three-Lug Short Action

The CM7S action uses the established Remington 700 short-action footprint with a three-lug bolt and 60-degree throw. The reduced bolt rotation limits handle travel and provides additional clearance around the optic during operation.

A one-piece .718-inch bolt body, M16-style extractor and integrated .300-inch recoil lug form the mechanical foundation of the 308 Barreled Action. Wire EDM-cut raceways establish uniform tolerances, while the oversized bolt knob and spiral-fluted bolt support smooth manual operation.

The action and bolt receive a full PVD coating for corrosion resistance and reduced operating friction. A pinned 20-MOA Picatinny rail provides a stable optic interface, while the large ejection port offers clear access to the chamber and action.

CM7S Action Specifications

• Footprint: Remington 700 short action
• Bolt design: Three lug
• Bolt throw: 60 degrees
• Extractor: M16 style
• Bolt construction: One piece
• Bolt-body diameter: .718 inch
• Bolt treatment: Spiral fluting
• Raceways: Wire EDM cut
• Optic rail: Pinned 20-MOA Picatinny
• Firing pin: .062 inch for compatibility with small-rifle-primer brass
• Recoil lug: Integrated .300 inch
• Fire-control removal: Tool-less
• Trigger compatibility: Remington 700 pattern
• Barrel thread: 1-1/16-inch-16
• Bolt stop: Side release
• Bolt knob: Oversized
• Action weight: Approximately 25 ounces
• Finish: Full PVD coating

Mos-Tek 16-Inch 1:8 Twist Barrel

The barrel is produced through CM’s collaboration with Mos-Tek. It is machined from 416R stainless steel, uses 5R rifling and receives E100 Blackout Cerakote for external protection.

The 1:8 twist provides a versatile choice for conventional supersonic 308 Winchester ammunition. The shouldered crown protects the muzzle, while 5/8×24 threads accept compatible muzzle devices, direct-thread suppressors and suppressor mounts.

The barrel installs with a Remage barrel nut and is supplied installed and headspaced on the CM7S action.

Barrel Specifications

• Cartridge: 308 Winchester
• Barrel length: 16 inches
• Material: 416R stainless steel
• Rifling: 5R
• Twist rate: 1:8
• Crown: Shouldered
• Muzzle threads: 5/8×24
• Barrel attachment: Remage barrel nut
• Finish: E100 Blackout Cerakote
• Complete barreled-action weight: 62.81 ounces or 3.92 pounds

308 Winchester is standardized by the Sporting Arms and Ammunition Manufacturers’ Institute. Ammunition must still be selected according to the barrel twist and intended use of the completed firearm.

Ammunition for the 1:8 Twist

The 1:8 twist makes this 308 Barreled Action the supersonic-first option in the CM7S barreled-action family. It supports conventional 308 Winchester ammunition across common hunting and target projectile weights.

CM also recommends this twist for subsonic projectiles weighing 220 grains or less. Heavier subsonic projectiles require substantially more rotational speed at their lower velocity.

CM’s 300-grain Maker REX measures 2.06 inches long and requires the 1:5 twist used in the CM7S 308 subsonic barreled action. Do not fire CM’s 300-grain subsonic ammunition through this 1:8 twist barrel, particularly with a suppressor attached.

The 308 Winchester Subsonic Guide explains the relationship between projectile length, velocity and barrel twist.

308 Winchester and 7.62×51 NATO

CM 308 Winchester firearms can use both 308 Winchester and appropriate 7.62×51 NATO ammunition. Although the cartridges are closely related, their published pressure information is obtained through different testing methods and should not be treated as universally interchangeable across every firearm.

Read the 308 Winchester vs 7.62 NATO Guide for CM’s complete compatibility explanation.

Completing the 308 Barreled Action

The CM7S uses the Remington 700 short-action footprint. A completed firearm requires a compatible trigger, chassis or stock, bottom metal and magazine.

• Chassis or stock: Remington 700 short-action inlet with clearance for the integrated .300-inch recoil lug
• Trigger: Compatible Remington 700-pattern trigger
• Bottom metal: Compatible with the selected chassis or stock and intended magazine system
• Magazine: Short-action AICS pattern when used with compatible bottom metal

The CM7S can use compatible polymer or metal short-action AICS magazines. The available 308 bolt-action magazine is a 10-round Magpul PMAG 7.62 AC selected for the CM7S platform.

When using a third-party chassis or stock, confirm Remington 700 short-action fit, recoil-lug clearance, trigger compatibility and magazine requirements with its manufacturer before ordering.

Suppressor Use

A bolt action does not use propellant gas to cycle, allowing the completed firearm to operate with or without a suppressor. CM generally recommends an enclosed suppressor because backpressure does not have to be balanced against semi-automatic bolt speed or receiver gas.

The suppressor must be rated for 308 Winchester, the 16-inch barrel and the intended firing schedule. Confirm muzzle-device compatibility, suppressor-to-bore alignment and manufacturer restrictions before firing.

The 308 Suppressor Guide explains CM’s recommendations across bolt-action, supersonic semi-automatic and subsonic semi-automatic platforms.

308 Winchester Guides

• What Is 308 Winchester?
• 308 bolt action vs semi auto
• 308 ballistics
• 308 barrel length
• 308 Winchester vs 7.62 NATO
• 308 suppressor guide
• Every 308 configuration in District 308

308 Barreled Action FAQ

Does this barreled action include a trigger?

No. A trigger is not included. The CM7S accepts compatible Remington 700-pattern triggers.

Will it fit a Remington 700 short-action stock or chassis?

The CM7S uses the Remington 700 short-action footprint with an integrated .300-inch recoil lug. Confirm that the selected chassis or stock provides the necessary recoil-lug clearance and supports the intended bottom metal and magazine system.

Can the 1:8 twist fire subsonic ammunition?

Yes. CM recommends subsonic projectiles weighing 220 grains or less with this 1:8 twist. Heavier subsonic projectiles, including CM’s 300-grain Maker REX, require the 1:5 twist used in the CM7S subsonic barreled action.

Does the barreled action require an FFL transfer?

Yes. The CM7S action is the serialized receiver, so the barreled action is a firearm and must transfer through a licensed dealer.

Can the completed firearm use a suppressor?

Yes. The barrel has 5/8×24 muzzle threads for compatible suppressor mounts and direct-thread suppressors. CM generally recommends an enclosed suppressor for a bolt-action firearm.

Who makes the 308 Barreled Action?

Chattahoochee Munitions manufactures the CM7S 308 Barreled Action, a 16-inch 1:8 twist 308 Winchester barreled action for Remington 700 short-action chassis and stocks. It is part of the Chattahoochee Munitions 308 Winchester line in District 308.

Why Choose This 308 Barreled Action?

Choose this 308 Barreled Action when the completed firearm will prioritize conventional supersonic ammunition with the flexibility to use appropriate subsonic projectiles weighing 220 grains or less. It combines a Mos-Tek 16-inch 1:8 twist barrel with CM’s three-lug, 60-degree action, wire EDM-cut raceways, pinned optic rail and full PVD coating.

For heavy subsonic projectiles, including CM’s 300-grain Maker REX, select the 12.5-inch 1:5 twist CM7S subsonic barreled action instead.