New AR: CMMG’s MkG-45 Guard in .45 ACP

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CMMG has released its new MkG-45 Guard, an innovative AR chambered in .45 ACP and featuring a unique Radial Delayed Blowback system.

CMMG has always been an innovator ever since its founding in 2002. However, in the past few years especially, it has really made an effort to redefine what the AR can be. In late 2014, the company introduced its Mk47 Mutant, a hybrid AR/AK design, and this past year, it brought out the MkW-15 Anvil in .458 SOCOM. Now, CMMG has just announced its new MkG-45 Guard, a .45 ACP pistol-caliber carbine.

The new MkG-45 Guard is offered in five different configurations and feeds from common Glock magazines. The gun also uses a unique, patent-pending Radial Delayed Blowback system that the company has developed.

“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. 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,” said Chris Reinkemeyer, CEO/CFO at CMMG.

Most pistol-caliber carbines feature a straight blowback operating system. In fact, CMMG's own Mk9 series of 9mm ARs utilizes a straight blowback design. However, CMMG found that a new system was needed with the larger, more potent .45 ACP.

The new Radial Delayed Blowback system on the CMMG MkG-45 Guard actually uses a bolt carrier group (BCG) not unlike those on a standard, direct impingement AR. However, its operation is different. Following a shot, it's the bolt's forced rotation to unlock that slows down the BCG enough to safely cycle .45 ACP loads. Without that delay for rotating and unlocking, the MkG-45 would be unable to safely handle the increased power of the .45 ACP. This system also permits the BCG and buffer system to be lighter than those on straight blowback 9mm ARs, which also translates to a lighter firearm overall.

The new MkG-45 utilizes AR-style controls, so lack of familiarity shouldn't be an issue. This also includes a last-round hold open function, which shooters are sure to appreciate. The Guard .45 ACP incorporates a new, patent-pending, dual-pinned, fully machined bolt catch linkage. This linkage should offer consistent and reliable operation without needing adjustments or tuning, and the actuation from this linkage is sturdy enough that it still uses a standard bolt catch spring.

The MkG-45 Guard ships with one 13-round factory Glock 21 magazine, and CMMG recommends factory double-stack Glock .45 ACP magazines if shooters are looking for additional mags. CMMG will also be offering bolt weight kits for shooters looking to fine-tune their gun for +P ammo or use with a suppressor.

For more information on the new CMMG MkG-45 Guard in .45 ACP, visit the CMMG website, or check out the specifications below.

Specifications:

CMMG MkG-45 Guard T
Type: Semi-auto, Radial Delayed Blowback
Caliber: .45 ACP
Barrel: 16.1 in., 1:16 twist, medium taper 4140 SBN barrel
Overall Length: 32.5 in. (stock collapsed)
Weight: 5.6 lbs. (unloaded)
Muzzle Device: CMMG SV Brake, threaded .578-28
Handguard: CMMG RKM11
Grip: A2-style pistol grip
Stock: Six-position M4-style
Lower Receiver: Billet 7075-T6 aluminum
Upper Receiver: Forged 7075-T6 Aluminum
Trigger: CMMG Single Stage GI-style trigger
MSRP: $1,299.95

CMMG MkG-45 Guard DRB
Type: Semi-auto, Radial Delayed Blowback
Caliber: .45 ACP
Barrel: 16.1 in., 1:16 twist, medium taper 4140 SBN barrel
Overall Length: 32.5 in. (stock collapsed)
Weight: 5.8 lbs. (unloaded)
Muzzle Device: CMMG SV Brake, threaded .578-28
Handguard: CMMG RKM14
Grip: Magpul MOE Pistol Grip
Stock: Magpul CTR stock
Lower Receiver: Billet 7075-T6 aluminum
Upper Receiver: Forged 7075-T6 Aluminum
Trigger: CMMG Single Stage GI-style trigger
MSRP: $1,399.95

CMMG MkG-45 Guard PDW
Type: Semi-auto, Radial Delayed Blowback
Caliber: .45 ACP
Barrel: 8 in., 1:16 twist, medium taper 4140 SBN barrel
Overall Length: 25 in. (stock collapsed)
Weight: 5 lbs. (unloaded)
Muzzle Device: CMMG SV Brake, threaded .578-28
Handguard: CMMG RKM7
Grip: Magpul MOE Pistol Grip
Stock: Magpul MOE adjustable stock
Lower Receiver: Billet 7075-T6 aluminum
Upper Receiver: Forged 7075-T6 Aluminum
Trigger: CMMG Single Stage GI-style trigger
MSRP: $1,349.95

MkG-45 Guard PDW Pistol
Type: Semi-auto, Radial Delayed Blowback
Caliber: .45 ACP
Barrel: 8 in., 1:16 twist, medium taper 4140 SBN barrel
Overall Length: 24 in. (stock collapsed)
Weight: 4.7 lbs. (unloaded)
Muzzle Device: CMMG SV Brake, threaded .578-28
Handguard: CMMG RKM7
Grip: Magpul MOE Pistol Grip
Stock: CMMG pistol receiver extension
Lower Receiver: Billet 7075-T6 aluminum
Upper Receiver: Forged 7075-T6 Aluminum
Trigger: CMMG Single Stage GI-style trigger
MSRP: $1,299.95

MkG-45 Guard DRB2
Type: Semi-auto, Radial Delayed Blowback
Caliber: .45 ACP
Barrel: 16.1 in., 1:16 twist, medium taper 4140 SBN barrel
Overall Length: 32.5 in. (stock collapsed)
Weight: 5.8 lbs. (unloaded)
Muzzle Device: CMMG SV Brake, threaded .578-28
Handguard: CMMG RKM14
Grip: Magpul MOE Pistol Grip
Stock: Magpul CTR stock
Lower Receiver: Billet 7075-T6 aluminum
Upper Receiver: Forged 7075-T6 Aluminum
Trigger: Geissele Automatics SSA
MSRP: $1,599.95

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