The CMMG Endeavor MK4 is a semi-automatic rifle chambered in .22 ARC with a 20-inch stainless steel barrel. The .22 ARC is a newer Hornady cartridge designed to push .22-caliber bullets to competitive long-range velocities from an AR platform, which makes the Endeavor MK4 an interesting option for varmint hunting and sport shooting. At 7 lbs and 37.8 inches overall, it's a full-size rifle. 
 

Key Specifications 

• Brand: CMMG 
• Model: Endeavor MK4 
• Caliber: .22 ARC 
• Barrel Length: 20 inches 
• Overall Length: 37.8 inches 
• Weight: 7 lbs 
• Capacity: 30+1 rounds 
• Condition: New in Box 
• Finish Per Color: Coyote Tan Cerakote (Receiver), Black (Stock) 
• Trigger Type: Zeroed Drop-In Single Stage 
• Stock Material: Magpul Synthetic 
• Muzzle Device: CMMG Zeroed Muzzle Brake 
   

Detailed Features 

• Stainless Steel Barrel: The 20-inch barrel is threaded, so you can add a suppressor or swap the muzzle device. The Black Nitride finish on the barrel, combined with Cerakote on the receiver, gives it corrosion resistance without requiring a lot of maintenance. 
   
• Zeroed Drop-In Trigger: CMMG's Zeroed single-stage trigger is a factory upgrade over a standard milspec trigger, with a cleaner break that benefits precision shooting. 
   
• CMMG Zeroed Muzzle Brake: The muzzle brake reduces felt recoil and keeps the muzzle from climbing during follow-up shots. 
   
• Magpul Stock: The Magpul stock is adjustable and familiar to most AR shooters, which means the rifle fits a wide range of shooters out of the box. 
   
• 30+1 Capacity: The 30-round magazine gives you extended sessions without interruption, which matters for target shooting and competition. 
   

Target Audience 

This rifle is for shooters who want a purpose-built .22 ARC platform from a known builder, specifically those interested in the caliber's long-range potential in a full-size AR. Varmint hunters and precision sport shooters are the primary audience.   

Owners of the CMMG Endeavor MK4 in .22 ARC and Coyote Tan report a generally positive experience, with build quality and performance as the top themes.

The .22 ARC chambering is still relatively new, and a lot of the discussion around this rifle focuses on the cartridge itself -- shooters interested in a purpose-built .22 ARC AR find the Endeavor MK4 a natural fit. Reliability and consistent groupings at the range come up often as positives.

The Coyote Tan Cerakote finish draws attention in a market dominated by black rifles. Most users find the aesthetics practical as well, since it doesn't show wear or dirt as visibly as black finishes.

Versatility gets mentioned -- users report using it for target work, small game, and training. The low recoil makes it accessible for newer shooters, but experienced shooters also find it useful for high-volume sessions.

The price is the recurring debate point. The Endeavor MK4 sits at a higher price than entry-level .22 or .223 rifles, and some buyers weigh whether the .22 ARC chambering and CMMG-specific features justify the premium. Most who made the purchase feel it does, but it's a common topic in forum discussions.

Customization interest is high. Users discuss optics, grips, and other AR-compatible accessories, and the threaded barrel opens the conversation about suppressor pairings.