CMMG Resolute Mk4 5_56x45mm 16_1in Rifle 55AC780-CT

CMMG Resolute Mk4 5.56x45mm Nato 16.1in Coyote Tan Rifle (55AC780-CT)

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  • CMMG Resolute Mk4 5.56x45mm Nato 16.1in Coyote Tan Rifle (55AC780-CT)
  • CMMG Resolute Mk4 5.56x45mm Nato 16.1in Coyote Tan Rifle (55AC780-CT)
  • CMMG Resolute Mk4 5.56x45mm Nato 16.1in Coyote Tan Rifle (55AC780-CT)

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  • 5.56x45mm NATO caliber
  • Direct impingement operating system
  • 4140CM, SBN barrel material
  • Mid gas port location
  • Cmmg EML15 M-Lok hand guard
  • Cmmg RipStock stock / brace
  • Mil-spec single stage trigger type
  • Mk4 Zeroed parts and accessories - Quality comes standard
  • Cerakote standard finish
  • Lifetime Quality Guarantee

When it comes to dimensions and the caliber, this is what comes to most people's minds when you say AR15. This Cmmg Resolute Mk4 5.56x45mm Nato 16.1" Rifle (55AC780) comes chambered in 5.56x45mm, one of the most prolific calibers in the world, and for good reason. 5.56, and its counterpart .223 Rem, have seen service with militaries, hunters, and recreational shooters for decades.

If you're after a particular look or have a certain AR accessory that fits you best then don't worry, this 5.56 Resolute is built on Cmmg's Mk4 platform and accepts virtually any and all AR15 accessories.

Fitted with the suite of ZEROED parts and accessories as well as our legendary RIPSTOCK, the Resolute is the rifle that’s never out of place. The new EML 15 handguard brings style to the next level. M-LOK attachment slots are found where expected at the 3, 6, and 9 o'clock positions as well as on top at 12 o'clock with the omission of a full-length Picatinny section found on our previous handguard. This reduces weight while the additional M-LOK section still gives shooters a place to mount those must have accessories.

The AR15 platform is well known for its capability for customization but picking the right parts doesn't have to be a nightmare of homework. Cmmg's ZEROED parts and accessories are made here in the USA with quality and attention to detail that is second to none and each RESOLUTE comes equipped with a slew of ZEROED parts standard, including: ZEROED Pistol Grip, ZEROED Trigger Guard, ZEROED 60 degrees /90 degrees Ambi Safety, ZEROED AR15 Ambi Charging Handle, ZEROED Ambi Mag Catch, ZEROED Extended Mag Release Button, ZEROED AR15 Bolt Catch, ZEROED AR15 Polymer Dust Cover, ZEROED Muzzle Brake 5.56mm.

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Warranty Information

Platform Mk4
Caliber 5.56x45mm NATO
Operating System Direct Impingement
Barrel Twist 1:7
Barrel Contour MT
Barrel Material 4140CM, SBN
Muzzle Device Cmmg Zeroed Muzzle Brake
Muzzle Thread 1/2 x 28
Gas Port Location Mid
Gas Block 0.750" Non-Adjustable
Upper Receiver Billet 6061 T6 Aluminum
Lower Receiver Mk4 Forged 7075 T6 Aluminum
Hand Guard Cmmg EML15 M-Lok
Finish Cerakote Standard
Charging Handle Cmmg Zeroed Ambi
Pistol Grip Cmmg Zeroed Pistol Grip
Buffer Type Carbine
Receiver Extension Cmmg 6 Position Fastback Extension
Stock / Brace Cmmg RipStock
Trigger Type Mil-Spec Single Stage
Trigger Guard Cmmg Zeroed Trigger Guard
Safety Selector Cmmg Zeroed 60/90 degree
Magazine Magpul 30rd Pmag
Barrel Length, in 16.1"
Length, in 32.5"
Weight, lbs 6.4
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Additional Information

Barrel Length:
5.56x45mm NATO
Capacity Rd.:
Coyote Tan
Product Type:
Serialized Item:
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