+1-800-504-5897 Help Center Check Order Status
About Us Policies Reviews How To
Free Shipping & Free Returns*

FREE SHIPPING on Over 250,000 Products

Shop now and get Free Value Shipping on most orders over $49 to the contiguous 48 states, DC, and to all U.S. Military APO/FPO/DPO addresses.

Enjoy our FREE RETURNS

We want to ensure that making a return is as easy and hassle-free as possible! If for any reason you are not satisfied with your purchase, simply return the item within 30 days of receipt, and we'll cover the cost of return shipping. Learn more about our Return Policy.

  • Entire Store
  • ...
  • Apparel & Footwear
  • Astronomy
  • Everything Else
  • Eyewear
  • Hunting Gear
  • Lab Equipment
  • Military Gear
  • Outdoor Gear
  • Photography Equipment
  • Police, EMS & Fire
  • Shooting
  • Sport Optics
  • Sports & Hobbies
TIP
Shopping Cart

CMMG Mk4 6mm ARC Resolute Upper Group Receiver Up to 14% Off w/ Free S&H — 3 models

CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Coyote Tan, 60B1091-CT
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Midnight Bronze, 60B1091-MB
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Tungsten, 60B1091-TNG
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Coyote Tan, 60B1091-CT
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Midnight Bronze, 60B1091-MB
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Tungsten, 60B1091-TNG
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Coyote Tan, 60B1091-CT
1 of 6 images
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Coyote Tan, 60B1091-CT
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Midnight Bronze, 60B1091-MB
2 of 6 images
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Midnight Bronze, 60B1091-MB
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Tungsten, 60B1091-TNG
3 of 6 images
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Tungsten, 60B1091-TNG
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Coyote Tan, 60B1091-CT
4 of 6 images
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Coyote Tan, 60B1091-CT
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Midnight Bronze, 60B1091-MB
5 of 6 images
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Midnight Bronze, 60B1091-MB
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Tungsten, 60B1091-TNG
6 of 6 images
CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Tungsten, 60B1091-TNG

Tap Tap to Zoom

Government Export Restriction Government Export Restriction
Government Restriction Government Restriction
Questions & Answers
This fits on a Milspec lower? Just need the Grendal mags? Correct?

Yes fits Mil-Spec lower and uses Grendel mags.

by Murphy, Verified Owner, July 31, 2025
Does this come with a complete bolt assembly and the charging handle? Expert Answer

Yes, the CMMG Mk4 6mm ARC Resolute Upper will include a BCG and charging handle.

by Ethan, Gear Expert, March 25, 2024
View All Q&A You Have a Question? Ask!

13% OFF AR Parts + 2% Bucks

See promotion details.
ARPARTYClick to Copy Coupon Code
Eligible models will have a savings offer and the coupon code to use below. Add the item to your cart and enter coupon code for savings on that select model! Expires in 19 hours. Cannot be combined with other promotions or offers.
3 Models Available
Color
All
Search

Product Info for CMMG Mk4 6mm ARC Resolute Upper Group Receiver

Chambered in 6mm ARC, this RESOLUTE Upper Group is designed to pair with any standard AR15 pattern lower group. Harness the capability of 6mm in this uniquely designed RESOLUTE 16.1 upper.image

WARNING: California`s Proposition 65

Specifications for CMMG Mk4 6mm ARC Resolute Upper Group Receiver:

Manufacturer: CMMG
Caliber: 6mm ARC
Overall Length: 16.5 in
Barrel Profile: Medium Tapered
Gas System Length: Pistol Length
Barrel Twist Rate: 1-7.5
Firearms Threads Per Inch: 5/8x24
Muzzle Device: CMMG Zeroed Muzzle Brake
Fabric/Material: 7075 T6 Aluminum
Gas Block Journal Size-Diameter: .750 in
Gun Rail: M-LOK
Gun Type: Rifle
Gun Make: CMMG
Gun Model: CMMG Mk4
Weight: 3.9 lb
Magazine Included: No
Mount Type: M-LOK

Package Contents:

  • CMMG Mk4 6mm ARC Resolute Upper Group Receiver

What firearm models does the manufacturer say CMMG Mk4 6mm ARC Resolute Upper Group Receiver is compatible with?

The manufacturer suggests that CMMG Mk4 6mm ARC Resolute Upper Group Receiver is compatible with CMMG Mk4

CMMG Mk4 6mm ARC Resolute Upper Group Receiver Orderable Models

List of Orderable Models

  • CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Coyote Tan, 60B1091-CT , MPN: 60B1091-CT , UPC: 810097504684 , Code: 2CM-URC-CP51-60B1091-CT
  • CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Midnight Bronze, 60B1091-MB , MPN: 60B1091-MB , UPC: 810097504691 , Code: 2CM-URC-CP51-60B1091-MB
  • CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Tungsten, 60B1091-TNG , MPN: 60B1091-TNG , UPC: 810097504721 , Code: 2CM-URC-CP51-60B1091-TNG

CMMG Mk4 6mm ARC Resolute Upper Group Receiver Unavailable & Discontinued Models

List of Unorderable Models

  • CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Titanium, 60B1091-TI , MPN: 60B1091-TI , UPC: 810097504714 , Code: 2CM-URC-CP51-60B1091-TI
  • CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Sniper Grey, 60B1091-SG , MPN: 60B1091-SG , UPC: 810097504707 , Code: 2CM-URC-CP51-60B1091-SG
  • CMMG Mk4 6mm ARC Resolute Upper Group Receiver, 16.1in, Charcoal Green, 60B1091-CG , MPN: 60B1091-CG , UPC: 810097504677 , Code: 2CM-URC-CP51-60B1091-CG
Compare (0)
1 item has been added
Add at least two items to compare