2016 may have been “the year of the pistol-caliber carbine,” though we don’t foresee 2017 slowing down on this trend. CMMG, which has a long history of making 9mm AR-15 components, has just branched out into a complete PCC chambered in the venerable .45 ACP. What’s more, it isn’t a straight blowback action but, rather, what CMMG is calling a “Radial Delayed Blowback” system. Press release follows . . .
CMMG Reveals Latest Innovation – The MkG45 GUARD
Boonville, MO – CMMG has announced the release of the MkG45 GUARD – a new AR15 rifle chambered in the iconic .45 ACP caliber. The GUARD is offered in five different configurations, operates on CMMG’s new, patent pending Radial Delayed Blowback system and is fed from Glock magazines.
“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.
While the straight blowback system found on most pistol-caliber AR carbines utilizes a non-rotating bolt assembly, the Radial Delayed Blowback system used on the GUARD has a bolt carrier group (BCG) that appears similar to that found on a direct impingement AR15 but operates completely differently. The rotating bolt is the key to the Radial Delayed Blowback system. It is the act of the bolt being forced to rotate and unlock that slows down the BCG just enough to safely cycle .45 ACP while keeping the BCG and buffer lighter than 9mm AR15’s.
Some advantages that result from this new operating system are that it reduces the overall weight of the rifle and simultaneously decreases the felt recoil by using a lighter bolt and buffer. It also opens up the door to run calibers that have historically been too powerful for straight blowback but weren’t suited for direct impingement.
CMMG also put a high emphasis on having fully functional AR15 controls, including last round hold open. The GUARD features an all new patent pending dual-pinned, fully machined bolt catch linkage. This linkage provides consistent and reliable operation straight out of the box with no need for adjustments or fine tuning. The actuation from this linkage is robust enough that it still uses a standard bolt catch spring.
The MkG45 GUARD comes with one 13-round factory Glock 21 magazine. For optimal reliability, CMMG recommends using factory double-stack GLOCK .45 ACP magazines. Bolt weight kits will be sold separately for those who wish to fine-tune the GUARD for +P ammunition or suppressor usage.
The CMMG MkG45 GUARD is available in the following configurations:
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: $1299.95MkG45 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: $1399.95MkG45 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: $1349.95MkG45 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: $1299.95MkG45 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: $1599.95CMMG Lifetime Quality Guarantee
CMMG, Inc. will guarantee its products against defects in material or workmanship. CMMG, Inc. will repair, replace or substitute part(s) (at CMMG, Inc. discretion) at no charge to the customer if a defect of material or workmanship is found. All service work must be carried out by CMMG, Inc.
About CMMG:
CMMG began in central Missouri in 2002 and quickly developed into a full-time business because of its group of knowledgeable and passionate firearms enthusiasts committed to quality and service. Its reputation was built on attention to detail, cutting edge innovation and the superior craftsmanship that comes from sourcing all their own parts. By offering high quality AR rifles, parts and accessories, CMMG’s commitment to top-quality products and professional service is as deep today as it was when it began.
For more information, please visit:
www.cmmginc.com.
https://www.facebook.com/CMMGInc
https://www.youtube.com/cmmg
It operates completely different from a rotating bolt by operating exactly like a rotating bolt. Way to reinvent the wheel, guys. Also, another PCC? Oh gosh… hard pass.
It’s a delayed blowback with rotating bolt. Most pistol caliber ARs have a straight blow back and the bolt carrier is one piece. This CMMG has a two piece carrier and bolt similar to an AR. Seems kind of cool to me.
Well in an AR it’s the carrier being pushed back that causes the bolt to rotate and eventually unlock. It sounds like, in this design, it’s force directly on the bolt that causes it to rotate and unlock and the carrier isn’t part of the equation. From the description, I don’t think their “similar but operates differently” assertion is a stretch.
Yep it seems the difference is there is no gas key and pressure through that to push back the carrier rotating the bolt. In this case like you said the cartridge pressure acts directly on the bolt forcing it to rotate. Which is the delay they speak of.
I wonder if the lugs on the bolt and the barrel extension are angled to allow the bolt to be pushed open by the case pushing on it, or if they’ve put some sort of bearings in there, or it’s more complicated with some type of gas piston system that rotates the bolt, etc etc. Apparently the mass of the bolt makes a difference, as the press release states that bolt weight kits can be used to fine-tune it for +P ammo or suppressed shooting. Interesting.
So, a delayed blow-back rotating bolt. Still a rotating bolt. Forgive me for being skeptical, but I’m not seeing the innovation that warrants that much money.
I agree, I’ll wait for a diagram but I think it seems more likely to be similar to say the Savage 1907.
I kind of (KIND OF) want a .45 PCC. I think a MSR chambered in .357 mag would be pretty neat.
But for $1400? Are you serious?
Right¿!
I don’t understand the engineering differences that keep the PCCs from being so expensive.
The only thing I can figure is that this niche is entirely market driven (‘duh¡).
I would love an AR based PCC; but my .40 Sub2000 is a third the cost, dead nuts accurate, very reliable, and most importantly FUN to shoot. Brings a grin to all (male/female/young/old) that take it for a spin.
The only carbine that “out grins” it is my Rossi 92 in .357.
True fun for one and all.
At one point there was someone wildcatting .357 Rimless Magnum. I really wanted a go at that! I think it would be amazingly fun to mess around with. I made a dummy round and it’s just sitting here :/
1300 bucks for a 45 acp pistol?
Let me know when its sub-1k.
this reeks of desperation
If I was going to get a PCC I’d do the CZ Scorpion EVO. And it’s $1,000.
I think a .357 Sig would be cool or even in 7.62×25 Tokarev would be sweet that’s a hot pistol caliber with a carbine length barrel. It’s got some velocity behind it.
I’d buy that for a dollar!
+1 for 7.62×25 Tokarev out of a PCC….. especially with those 85gr. Prvi Partizan JHPs that work quite well on kudzu pigs out of a standard TT33.
If I was a lot better at machining, I’d work up one of those carbine conversions for a Tokarev, like I see for GLOCKs. And just for giggles, I’d make it look like a Kel-Tec; everyone would want one, but never be able to find one.
CA legal? JK.
Wow! Takes standard Glock 21 mags!
Know what else takes standard Glock 21 mags?
Glock 21!
Or a Vector, JRC, Thureon, Lone Wolf, TNW…
And how many of these have the hold open implemented?
For that money you can get a real AR or a proper pistol.
Shit. You could get TWO good ARs for that price, or like 4 glock 21s. Or one good AR and two glocks.
Curious to see how the bolt actually works. If it’s legitimately better than straight blowback, I could see this design becoming a new standard. The AR-based PCC has never worked well enough for me.
It is a real delayed blowback, with a 2-piece bolt group, where a head is locked, but moves a small amount, and exerts pressure on a larger part through a mechanical disadvantage. In HK, the disadvantage is the angle against which rollers act. In Kirali it’s a basic lever. In Guard, the disadvantage is actually the cam track in the carrier. As the bolt rotates, it tries to accelerate the carrier back through the cam pin. This way the BCG in Guard is much lighter than the bolt in Thompson or Grease Gun. By the time the bolt rotates enough to unlock, bullet has long left the barrel and it’s not longer exerting any pressure on the carrier. Instead, the inertia of the carrier continues to unlock the bolt through the same cam track (only its opposite side).
I will say that this certainly needs a can to be cool enough to spend $1200 on.
I love all the naysayers that really have no idea what it costs to build a PCC. These are expensive to build. A good quality purpose built lower with LRBHO is expensive. Other parts are pricey as well. Its easy to drop $450 just on a quality lower and a good bolt. Add in a decent upper for $200 with a handguard and it adds up fast. Well I guess you could just go the PSA route, buy some crap, throw it together and hope it works, and save a few hundred.
Look at a Sig MPX. They are pricey, but probably one the best PCC’s out there. We wont even go into HK’s for price. Yes, the CZ Scorp is less money, but its not nearly as refined as an MPX or a well built PCC on the AR platform.
Good on CMMG for building something that is reasonably priced, should see $1100ish for street price. I hope they build one in 10mm as direct blowback 10mm is a little hot for. The only thing I dont like about it? Glock mags. Id prefer an SMG style mag like a UMP or MAC as they tend to be more reliable for LRBHO.
The problem with SMG mags is that they never have provisions for a bolt hold-open, because it’s unnecessary when firing in burts: if your gun stops firing before you release the trigger, it all you need to know to reload.
Plus most SMG fired from an OPEN BOLT!!!