Comment(s)

CMMG has announced that—after durability testing—its MkG GUARD pistol caliber carbine in .45 ACP, which is fed from factory Glock magazines, is now safely rated for 450 SMC. More on that round below, via the presser:

For those unfamiliar with 450 SMC, Triton first conceived the cartridge in 2001. The design was ultimately taken over and completed by DoubleTap ammunition years later. In essence, it is a magnum version of .45 ACP that offers ballistics that are comparable to 10mm. It is a true “stopper” that delivers energy capable of taking down big game.

While the 450 SMC uses a case with the same outer dimensions as .45 ACP, there are a few significant differences that allow DoubleTap to load 450 SMC with five to six thousand pounds per square inch of pressure more than a standard .45ACP. First, the 450 SMC uses a small magnum rifle primer instead of the large pistol primer. This modification allows the hardened case to be thicker at the base. Second, the brass is manufactured from the ground up to handle up to 30,000 pounds of pressure. The result is a dual-purpose cartridge that is exceptional for both hunting and personal defense.

The company notes that while 450 SMC can be run in any .45 ACP rifle rated for +P ammo, the rearward force created by the load would cause issues in a straight blowback AR15. The MkG GUARD is able to mitigate those issues due to its Radial Delayed Blowback system.

The Radial Delayed Blowback system uses up some of the recoil impulse of the spent round to unlock the rotating bolt from the barrel extension. This mitigates the leftover rearward force that then drives the carrier back to cycle the action. By eliminating some of this rearward force during the unlocking sequence, the GUARD requires less weight in the bolt carrier group and buffer to safely cycle. This reduction in reciprocating mass results in less felt recoil for the end user.

See below to check out how the 450 SMC compares to the 10mm out of a 16-inch barrel, according to data supplied to CMMG by DoubleTap. In addition see the specs for CMMG’s MkG GUARD platform. For more, visit cmmginc.com.

450 SMC Performance

Load Muzzle Velocity Muzzle Energy
450 SMC 160gr. Barnes TAC-XP Lead Free 1,740 FPS 1,076 Ft. Lbs.
450 SMC 185gr. Bonded Defense JHP 1,725 FPS 1,223 Ft. Lbs
450 SMC 230gr. Bonded Defense JHP 1,400 FPS 1,001 Ft. Lbs.
450 SMC 255gr. Hardcast Solid 1,300 FPS 958 Ft. Lbs.

10mm Performance

Load Muzzle Velocity Muzzle Energy
10mm 165gr. Bonded Defense JHP 1,700 FPS 1,059 Ft. Lbs.
10mm 180gr. Bonded Defense JHP 1,600 FPS 1,023 Ft. Lbs
10mm 200gr. Hardcast Solid 1,590 FPS 1,123 Ft. Lbs.
10mm 230gr. Hardcast Solid 1,350 FPS 931 Ft. Lbs.

 

MkG45 GUARD T

  • BARREL: 16.1″ 1:16 Twist, Medium Taper 4140 SBN Barrel
  • MUZZLE: CMMG SV Brake, Threaded .578-28
  • HAND GUARD: CMMG RKM11
  • FURNITURE: A2 Pistol Grip, M4 butt stock with 6-pos mil-spec receiver extension
  • RECEIVERS: Billet 7075-T6 AL Lower, Forged 7075-T6 AL Upper
  • TRIGGER: CMMG Single Stage Mil-Spec style trigger
  • WEIGHT: 5.6 lbs (UNLOADED)
  • LENGTH: 32.5 (STOCK COLLAPSED)
  • MSRP: $1299.95

MkG45 GUARD DRB

  • BARREL: 16.1″ 1:16 Twist, Medium Taper 4140 SBN Barrel
  • MUZZLE: CMMG SV Brake, Threaded .578-28
  • HAND GUARD: CMMG RKM14
  • FURNITURE: Magpul MOE Pistol Grip, Magpul CTR stock with 6-pos mil-spec receiver extension
  • RECEIVERS: Billet 7075-T6 AL Lower, Forged 7075-T6 AL Upper
  • TRIGGER: CMMG Single Stage Mil-Spec style trigger
  • WEIGHT: 5.8 lbs (UNLOADED)
  • LENGTH: 32.5 (STOCK COLLAPSED)
  • MSRP: $1399.95

MkG45 GUARD PDW

  • BARREL: 8″ 1:16 Twist, Medium Taper 4140 SBN Barrel
  • MUZZLE: CMMG SV Brake, Threaded .578-28
  • HAND GUARD: CMMG RKM7
  • FURNITURE: Magpul MOE Pistol Grip, Magpul MOE stock with 6-pos mil-spec receiver extension
  • RECEIVERS: Billet 7075-T6 AL Lower, Forged 7075-T6 AL Upper
  • TRIGGER: CMMG Single Stage Mil-Spec style trigger
  • WEIGHT: 5 lbs (UNLOADED)
  • LENGTH: 25 (STOCK COLLAPSED)
  • MSRP: $1349.95

MkG45 GUARD PDW Pistol

  • BARREL: 8″ 1:16 Twist, Medium Taper 4140 SBN Barrel
  • MUZZLE: CMMG SV Brake, Threaded .578-28
  • HAND GUARD: CMMG RKM7
  • FURNITURE: Magpul MOE Pistol Grip, CMMG Pistol receiver extension
  • RECEIVERS: Billet 7075-T6 AL Lower, Forged 7075-T6 AL Upper
  • TRIGGER: CMMG Single Stage Mil-Spec style trigger
  • WEIGHT: 4.7 lbs (UNLOADED)
  • LENGTH: 24″ (STOCK COLLAPSED
  • MSRP: $1299.95

MkG45 GUARD DRB2

  • BARREL: 16.1″ 1:16 Twist, Medium Taper 4140 SBN Barrel
  • MUZZLE: CMMG SV Brake, Threaded .578-28
  • HAND GUARD: CMMG RKM14
  • FURNITURE: Magpul MOE Pistol Grip, Magpul CTR stock with 6-pos mil-spec receiver extension
  • RECEIVERS: Billet 7075-T6 AL Lower, Forged 7075-T6 AL Upper
  • TRIGGER: Giessele Automatics SSA
  • WEIGHT: 5.8 lbs (UNLOADED)
  • LENGTH: 32.5 (STOCK COLLAPSED)
  • MSRP: $1599.95

Up Next

Dom Raso: Retired US Navy SEAL Defends AR-15 Use for All Americans

Retired US Navy SEAL Dom Raso stands firm in support of our country's greatest assets...