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CMMG Mk4 Resolute Upper Receiver Group Up to 21% Off w/ Free S&H — 6 models

CMMG Mk4 Resolute Upper Receiver Group, .22 Long Rifle, 17in, Armor Black, 22B83CC-AB
CMMG Mk4 Resolute Upper Receiver Group, .300 AAC Blackout, 16.1in, Armor Black, 30B12BB-AB
CMMG Mk4 Resolute Upper Receiver Group, 5.56x45mm NATO, 16.1in, Armor Black, 55BC7C3-AB
CMMG Mk4 Resolute Upper Receiver Group, 6.5mm Grendel, 16.1in, Armor Black, 64BCF88-AB
CMMG Mk4 Resolute Upper Receiver Group, 6mm ARC, 16.1in, Armor Black, 60B1091-AB
CMMG Mk4 Resolute Upper Receiver Group, .350 Legend, 16.1in, Armor Black, 35B5FBC-AB
CMMG Mk4 Resolute Upper Receiver Group, .22 Long Rifle, 17in, Armor Black, 22B83CC-AB
CMMG Mk4 Resolute Upper Receiver Group, .300 AAC Blackout, 16.1in, Armor Black, 30B12BB-AB
CMMG Mk4 Resolute Upper Receiver Group, 5.56x45mm NATO, 16.1in, Armor Black, 55BC7C3-AB
CMMG Mk4 Resolute Upper Receiver Group, 6mm ARC, 16.1in, Armor Black, 60B1091-AB
CMMG Mk4 Resolute Upper Receiver Group, .350 Legend, 16.1in, Armor Black, 35B5FBC-AB
CMMG Mk4 Resolute Upper Receiver Group, .22 Long Rifle, 17in, Armor Black, 22B83CC-AB
1 of 11 images
CMMG Mk4 Resolute Upper Receiver Group, .22 Long Rifle, 17in, Armor Black, 22B83CC-AB
CMMG Mk4 Resolute Upper Receiver Group, .300 AAC Blackout, 16.1in, Armor Black, 30B12BB-AB
2 of 11 images
CMMG Mk4 Resolute Upper Receiver Group, .300 AAC Blackout, 16.1in, Armor Black, 30B12BB-AB
CMMG Mk4 Resolute Upper Receiver Group, 5.56x45mm NATO, 16.1in, Armor Black, 55BC7C3-AB
3 of 11 images
CMMG Mk4 Resolute Upper Receiver Group, 5.56x45mm NATO, 16.1in, Armor Black, 55BC7C3-AB
CMMG Mk4 Resolute Upper Receiver Group, 6.5mm Grendel, 16.1in, Armor Black, 64BCF88-AB
4 of 11 images
CMMG Mk4 Resolute Upper Receiver Group, 6.5mm Grendel, 16.1in, Armor Black, 64BCF88-AB
CMMG Mk4 Resolute Upper Receiver Group, 6mm ARC, 16.1in, Armor Black, 60B1091-AB
5 of 11 images
CMMG Mk4 Resolute Upper Receiver Group, 6mm ARC, 16.1in, Armor Black, 60B1091-AB
CMMG Mk4 Resolute Upper Receiver Group, .350 Legend, 16.1in, Armor Black, 35B5FBC-AB
6 of 11 images
CMMG Mk4 Resolute Upper Receiver Group, .350 Legend, 16.1in, Armor Black, 35B5FBC-AB
CMMG Mk4 Resolute Upper Receiver Group, .22 Long Rifle, 17in, Armor Black, 22B83CC-AB
7 of 11 images
CMMG Mk4 Resolute Upper Receiver Group, .22 Long Rifle, 17in, Armor Black, 22B83CC-AB
CMMG Mk4 Resolute Upper Receiver Group, .300 AAC Blackout, 16.1in, Armor Black, 30B12BB-AB
8 of 11 images
CMMG Mk4 Resolute Upper Receiver Group, .300 AAC Blackout, 16.1in, Armor Black, 30B12BB-AB
CMMG Mk4 Resolute Upper Receiver Group, 5.56x45mm NATO, 16.1in, Armor Black, 55BC7C3-AB
9 of 11 images
CMMG Mk4 Resolute Upper Receiver Group, 5.56x45mm NATO, 16.1in, Armor Black, 55BC7C3-AB
CMMG Mk4 Resolute Upper Receiver Group, 6mm ARC, 16.1in, Armor Black, 60B1091-AB
10 of 11 images
CMMG Mk4 Resolute Upper Receiver Group, 6mm ARC, 16.1in, Armor Black, 60B1091-AB
CMMG Mk4 Resolute Upper Receiver Group, .350 Legend, 16.1in, Armor Black, 35B5FBC-AB
11 of 11 images
CMMG Mk4 Resolute Upper Receiver Group, .350 Legend, 16.1in, Armor Black, 35B5FBC-AB

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Questions & Answers
Does this come with the bcg and charging handle Expert Answer

The CMMG Mk4 Resolute Upper Receiver Group comes with a BCG and Charging Handle.

by Hunter, Gear Expert, September 28, 2023
See 1 More Answer
does it come with bcg Expert Answer

Yes, the CMMG Mk4 Resolute Upper Receiver Group will include a BCG as well as a charging handle.

by Ethan, Gear Expert, March 10, 2023
View All Q&A You Have a Question? Ask!
Customer Reviews
Helpful Positive Review
Not prefect but still good. by Doug, Verified Owner, February 1, 2023
Works great. Easy to install. Only complaint is it came with a small blemish on the receiver (Optics Planet may be getting CMMG blems). Once installed you couldn't see it unless it was pointed out. Love ambidextrous charge handle.
3/3 found this helpful
Helpful Positive Review
very accurate and reliable by dan, Verified Owner, April 7, 2023
I used a sprinco red spring and it cycled perfectly with 4 o’clock ejection firing winchester 145gr fmj. Relatively lightweight and streamlined good looks. On my POF lower it looks awesome! The ambi Charging handle is great for my scoped rifle as i t...
Read More...
1/1 found this helpful
Most Recent Reviews
Great 22 upper by Ken S, March 15, 2025
Works great. Expected quality and precision from CMMG!
Read All 3 Reviews

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Product Info for CMMG Mk4 Resolute Upper Receiver Group

Top off your next build with this RESOLUTE Mk4 Upper Group. Chambered, this upper group is a staple for any collection and comes ready to pair with the AR15 lower group of your choice.image

WARNING: California`s Proposition 65

Specifications for CMMG Mk4 Resolute Upper Receiver Group:

Manufacturer: CMMG
Muzzle Device: CMMG Zeroed Muzzle Brake
Color: Armor Black
Fabric/Material: Billet 6061 T6 Aluminum
Gas Block Journal Size-Diameter: .750 in
Gun Rail: M-LOK
Gun Type: Rifle
Gun Make: CMMG
Gun Model: CMMG Mk4
Condition: New
Magazine Included: No

Package Contents:

  • CMMG Mk4 Resolute Upper Receiver Group

What firearm models does the manufacturer say CMMG Mk4 Resolute Upper Receiver Group is compatible with?

The manufacturer suggests that CMMG Mk4 Resolute Upper Receiver Group is compatible with CMMG Mk4

CMMG Mk4 Resolute Upper Receiver Group Orderable Models

List of Orderable Models

  • CMMG Mk4 Resolute Upper Receiver Group, .22 Long Rifle, 17in, Armor Black, 22B83CC-AB , MPN: 22B83CC-AB , UPC: 810097502024 , Code: 2CM-URC-CMK22-22B83CC-AB
  • CMMG Mk4 Resolute Upper Receiver Group, 5.56x45mm NATO, 16.1in, Armor Black, 55BC7C3-AB , MPN: 55BC7C3-AB , UPC: 810097503823 , Code: 2CM-URC-CMK22-55BC7C3-AB
  • CMMG Mk4 Resolute Upper Receiver Group, 6.5mm Grendel, 16.1in, Armor Black, 64BCF88-AB , MPN: 64BCF88-AB , UPC: 810097504738 , Code: 2CM-URC-CMK22-64BCF88-AB
  • CMMG Mk4 Resolute Upper Receiver Group, .350 Legend, 16.1in, Armor Black, 35B5FBC-AB , MPN: 35B5FBC-AB , UPC: 810097502635 , Code: 2CM-URC-CMK22-35B5FBC-AB
  • CMMG Mk4 Resolute Upper Receiver Group, 6mm ARC, 16.1in, Armor Black, 60B1091-AB , MPN: 60B1091-AB , UPC: 810097504660 , Code: 2CM-URC-CMK22-60B1091-AB
  • CMMG Mk4 Resolute Upper Receiver Group, .300 AAC Blackout, 16.1in, Armor Black, 30B12BB-AB , MPN: 30B12BB-AB , UPC: 810097502420 , Code: 2CM-URC-CMK22-30B12BB-AB

CMMG Mk4 Resolute Upper Receiver Group Unavailable & Discontinued Models

List of Unorderable Models

  • USED, CMMG Mk4 Resolute Upper Receiver Group, 7.62x39mm, 16.1in, Armor Black, 76BFCB4-AB , MPN: 76BFCB4-AB-EDEMO , Code: 2CM-URC-CMK22-76BFCB4-AB-EDEMO-IN-U
  • CMMG Mk4 Resolute Upper Receiver Group, 7.62x39mm, 16.1in, Armor Black, 76BFCB4-AB , MPN: 76BFCB4-AB , UPC: 810097504943 , Code: 2CM-URC-CMK22-76BFCB4-AB
  • USED CMMG Mk4 Resolute Upper Receiver Group, 7.62x39mm, 16.1in, Armor Black, 76BFCB4-AB, EDEMO1, Used, Condition Fair , MPN: 76BFCB4-AB-EDEMO1 , Code: 2CM-URC-CMK22-76BFCB4-AB-EDEMO1
  • DEMO, CMMG Mk4 Resolute Upper Receiver Group, 7.62x39mm, 16.1in, Armor Black, 76BFCB4-AB , MPN: 76BFCB4-AB-DEMO , Code: 2CM-URC-CMK22-76BFCB4-AB-DEMO
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