"With the Guard, we set out to engineer an affordable, highly reliable AR chambered in .45 ACP that would use the widely-available Glock magazines," said Chris Reinkemeyer, CEO/CFO of CMMG. "In the early stages of design, we tested out a variety of different operating systems, including straight blowback and direct impingement, but none of those options gave us the reliability we were looking for. We ultimately came up with the design for the Radial Delayed Blowback system and from there, all the pieces started falling into place."
The company's Radial Delayed Blowback system uses a bolt-carrier group similar in appearance to those found on standard AR-15s, but the operation of the patent-pending system is different from standard BCGs. The rotating bolt found on the new gun must rotate to unlock the system, slowing down the system enough to cycle the .45 ACP rounds safely and reliably.
The benefits of this new system include a reduced overall weight, since the BCG and the buffer can be made lighter than those found on other pistol-caliber carbines. The new system also allows for the development of similar firearms chambered in calibers deemed too powerful for use in a straight-blowback system but couldn't be used in a direct-impingement setup.
Other features of the new CMMG MkG45 Guard include the use of standard AR-15 controls and features, including a bolt hold open. The company incorporated a new bolt-catch linkage that is designed to provide users with reliable operation without the need for added refinement. The system still uses a standard bolt-catch spring.
Five models of the new CMMG Guard pistol-caliber carbine are available. The first model is the MkG45 Guard T, which features a 16.1-inch barrel equipped with a CMMG SV muzzle brake. The rifle uses a CMMG RKM11 handguard and a standard A2-style pistol grip and M4 butt stock. The trigger is a single-stage mil-spec trigger from the company. Total length and weight of the gun is 32.5 inches and 5.6 pounds, respectively. The suggested retail price on the T model is $1,299.95.
The company also offers the MkG45 Guard PDW and the PDW Pistol. The two guns come equipped with an 8-inch barrel equipped with a CMMG SV brake and the company's RKM7 handguard. The PDW is equipped with a Magpul MOE pistol grip and stock, while the pistol is equipped with the MOE pistol grip and a CMMG pistol receiver extension. The PDW model measures in at 25 inches and weighs 5 pounds, and the pistol measures 24 inches and weighs just 4.7 pounds. The suggested retail price on the MkG45 Guard PDW Pistol is $1,299.95, while the PDW model retails at a suggested price of $1,349.95.
Finally, CMMG offers the MkG45 Guard DRB and DRB2. These two pistol-caliber carbines feature a 16.1-inch barrel and are both equipped with the CMMG SV brake and a RKM14 handguard, Magpul MOE pistol grip and a CTR stock. Both guns measure 32.5 inches in length and both guns weigh 5.8 pounds. The difference between the two models can be found inside the lower receiver. The DRB comes equipped with a single-stage mil-spec trigger, while the DRB2 comes factory-equipped with a Geissele Automatics SSA trigger. The suggested retail price of the DRB is $1,399.95, while the DRB2 retails at a suggested price of $1,599.95.