Not only is 9mm one of the most prolific calibers for handguns 9mm also makes a great choice for your next pistol caliber carbine. Although this CMMG RESOLUTE uses the same 9mm Radial Delayed Blowback upper system as our other 9mm RESOLUTES and BANSHEES this Mk4 RESOLUTE is unique in the fact that it uses our 9mm AR Conversion magazines. What�s the benefit of using an AR15 lower receiver? By swapping the upper group and magazine you can change the caliber of your rifle in seconds. - When full-size rifles are too cumbersome and pistols/SBRs don�t deliver the long-range ballistic performance you need the CMMG RESOLUTE line of carbine length rifles is the answer. 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. With a range of choices just pick the caliber you need for the job and let your rifle do the talking. - Platform: Mk4 - Caliber: 9mm - Operating System: Radial Delayed Blowback - Barrel Length: 16.1 - Barrel Twist: 1:10 - Barrel Contour: MT - Barrel Material: 4140CM SBN - Muzzle Device: CMMG ZEROED Muzzle Brake - Muzzle Thread: 1/2 X 28 - 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: CMMG 9mm Conversion - Weight: 6.2 - Length: 32.8