CM15 6.5 Grendel Precision Rifle 20″ – FDE Metallic Cerakote

Chattahoochee Munitions manufactures the CM15 20-inch 6.5 Grendel precision rifle, an AR15-pattern semi-automatic configured for longer, more deliberate shots. This FDE Metallic configuration combines a straight-fluted 416R stainless barrel with a 1:8 twist, a rifle-length gas system, a 15-inch free-float M-LOK handguard, and a TriggerTech AR15 Duty trigger, at 7 lb 4 oz with an unloaded magazine.

Explore the complete Chattahoochee Munitions 6.5 Grendel lineup at Grendel’s Lair, and read the 6.5 Grendel guide for how ballistic coefficient and velocity work together.

Designed as a 6.5 Grendel Precision Rifle

Precision depends on the whole system: barrel, ammunition, trigger, optic, and shooter. This 6.5 Grendel precision rifle gives you a free-floated 20-inch 416R stainless barrel, a full-length top Picatinny rail for a magnified optic, and a two-stage TriggerTech AR15 Duty option for a clean, predictable break. The B5 Systems Bravo stock adjusts for length of pull from 11.00 to 14.25 inches.

A longer barrel does not by itself guarantee accuracy; ammunition consistency matters as much. The 6.5 Grendel barrel length comparison covers what changes between barrel lengths, and 6.5 Grendel vs 6mm ARC compares two efficient AR15 precision cartridges.

Barrel and Gas System

The 20-inch 416R stainless steel barrel is straight-fluted, finished in E100 Blackout Cerakote, and cut with a 1:8 twist that stabilizes the common range of 6.5 Grendel bullets. It runs a rifle-length gas system with a .750-inch gas journal, a Melonite gas tube, and a Superlative Arms adjustable gas block. A shouldered crown and 5/8×24 threads accept a muzzle device or suppressor. Because the CM15 is gas operated, Chattahoochee Munitions recommends a flow-through suppressor to limit back pressure, and the adjustable gas block and Odin adjustable buffer help tune the rifle for suppressed use.

Receivers, Bolt, and Trigger

CNC-machined 7075-T6 billet receivers carry an integral trigger guard, a flared magazine well, and ambidextrous safety, magazine release, and bolt release. The CM15 Low Mass bolt carrier group uses a 9310 steel bolt manufactured to the Grendel Type II specification, with nitride-coated bolt, carrier, and gas key. Fire control is a TriggerTech AR15 Duty trigger in single-stage straight, single-stage curved, or two-stage straight, each at 3.5 lb total pull.

FDE Metallic Cerakote Finish

This 6.5 Grendel Precision Rifle is finished in FDE Metallic Cerakote on the upper and lower receivers, buffer tube, and handguard, with a Coyote B5 Systems Bravo stock, grip, and rail covers. Every CM15 20-inch 6.5 Grendel shares the same mechanical specifications; only the finish differs. One 10-round 6.5 Grendel AR15 magazine is included.

CM15 20-Inch 6.5 Grendel Specifications

• Manufacturer: Chattahoochee Munitions
• Platform: CM15 AR15-pattern semi-automatic rifle
• Chambering: 6.5 Grendel
• Barrel: 20-inch 416R stainless steel, straight-fluted, E100 Blackout Cerakote
• Twist rate: 1:8
• Muzzle: 5/8×24 threads, shouldered crown
• Gas system: Rifle-length, .750-inch gas journal, Melonite gas tube
• Gas block: Superlative Arms adjustable
• Buffer: Odin adjustable AR15 buffer, CM mil-spec buffer tube, QD endplate
• Bolt carrier group: CM15 Low Mass BCG; 9310 steel bolt manufactured to the Grendel Type II specification, HPT/MPI tested; nitride bolt, carrier, and gas key; tool-steel extractor
• Receivers: CNC-machined 7075-T6 billet upper and lower, integral trigger guard, flared magazine well
• Controls: Ambidextrous safety, magazine release, and bolt release
• Charging handle: CM15 ambidextrous 7075 charging handle, made in collaboration with Breek Arms
• Trigger: TriggerTech AR15 Duty: single-stage straight, single-stage curved, or two-stage straight; 3.5 lb total pull
• Handguard: 15-inch CM15 LWS M-LOK, dual-taper attachment with steel barrel nut, M-LOK sides and bottom, full-length top Picatinny rail, QD sockets at 3 and 9 o’clock
• Stock and grip: B5 Systems Bravo stock, B5 grip and rail covers
• Finish: FDE Metallic Cerakote on the upper and lower receivers, buffer tube, and handguard, with a Coyote B5 Systems stock, grip, and rail covers
• Magazine: One 10-round DURAMAG 6.5 Grendel AR15-pattern magazine
• Weight: 7 lb 4 oz with unloaded magazine, no accessories (listing weight is for shipping)
• Overall length: 37.50–40.75 inches
• Length of pull: 11.00–14.25 inches

Frequently Asked Questions

Who makes a 6.5 Grendel precision rifle?

Chattahoochee Munitions manufactures the CM15 20-inch 6.5 Grendel precision rifle with a free-float 1:8 twist 416R stainless barrel, rifle-length gas system, full-length top Picatinny rail, and a two-stage TriggerTech AR15 Duty trigger option.

What twist rate does the CM15 20-inch 6.5 Grendel use?

A 1:8 twist, which stabilizes the common range of 6.5 Grendel bullets from lighter predator loads to heavier hunting bullets.

What gas system does it use?

A rifle-length gas system with a .750-inch gas journal and a Superlative Arms adjustable gas block.

What magazine does the CM15 6.5 Grendel use?

A 6.5 Grendel AR15-pattern magazine. One 10-round 6.5 Grendel AR15 magazine is included. CM15 and CM7S magazines are not interchangeable.

What suppressor does Chattahoochee Munitions recommend for the CM15?

A flow-through suppressor. The CM15 is gas operated, and a flow-through design limits back pressure so the rifle is easier to tune. Confirm the suppressor is rated for 6.5 Grendel and the barrel length.

What bolt does it use?

A CM15 Low Mass bolt carrier group with a bolt manufactured to the Grendel Type II specification. It is not interchangeable with the CM7S bolt-action bolt.

Does the finish change performance?

No. All CM15 20-inch 6.5 Grendel rifles share the same mechanical specifications; Black Tungsten Cerakote, Cobalt Kinetics Green Cerakote, and FDE Metallic Cerakote differ only in color.

How much does it weigh?

7 lb 4 oz with an unloaded magazine and no accessories. Any heavier listing weight is the shipping weight.