The Mk4 HT Upper Group features CMMG’s RKM11 KeyMod free float hand guard. Either a 416 stainless or nitrided 4140 CrMo steel barrels in a heavy taper profile are offered in 5.56mm and 300 BLK. The 22LR model is only available in the nitrided 4140 CrMo type barrel. For best performance use a round style […]READ MORE
The Mk4 T Upper Group introduces CMMG’s RKM series of KeyMod free float hand guards. Either a 416 stainless or nitrided 4140 CrMo steel barrel in a medium taper profile are offered for both 5.56mm and 300 BLK. The 22LR and 9mm models feature a nitrided 4140 CrMo M4 profile barrel. For best performance use […]READ MORE
The classic AR15 Upper Group configuration, based on the M16A4, is available in both 5.56x45mm NATO and 22LR. The Mk4 A4 Upper Group’s defining characteristic is its 20″ government profile barrel. The 5.56mm barrel is chrome-lined and built to the military’s stringent specifications, while the 22LR features a premium 4140 CrMo steel barrel with a […]READ MORE
The Mk4 PDW Upper Group is CMMGs smallest, most compact upper group equipped with the RKM7 KeyMod free floating hand guard and a nitrided 4140 CrMo steel barrel. This Upper Group is available in 300 BLK, 9mm Luger and 22LR; every Upper Group is covered by CMMGs lifetime quality guarantee. For best performance use a […]READ MORE
The Mk4LE Optics Ready Upper Group is set up for your favorite scope or red dot sight as it has no front sight base to interfere with the sight picture. The Mk4LE OR comes with CMMG’s lifetime quality guarantee. For best performance use a round style hammer as notched hammers can cause function issues and […]READ MORE
The iconic Mk4LE Upper Group is available in 5.56x45mm, 300 AAC BLK, 9mm Luger and 22LR. They all feature a nitrided 16.1″ 4140 CrMo steel barrel in a M4 profile except the 300 BLK as it features a M300 multi-role barrel profile. The standard configuration includes a “F” marked front sight base. For best performance […]READ MORE
Firearms may only be shipped to a licensed dealer (FFL Holder). Actual buyer must pick up from FFL dealer who will conduct the background check. Some listed items may not be legal in every state. We will not sell firearms to residents of CA or NY. Buyer assumes responsibility of knowing purchase laws in their state. You must be at least 18 years of age to purchase a rifle, and 21 years of age to purchase a handgun or receiver. A CMMG Representative will contact you after your order has been placed to facilitate the transfer.
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