CMMG 9MM Questions

Fret

USAF Retired
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Minuteman
Nov 14, 2017
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N Idaho
I'm thinking of getting a CMMG Guard AR pistol with 8" barrel for suppressor use. It's supposed to be quieter than the regular blowback 9mm since their modified bolt is delayed a bit. Have any of you used one of these with a suppressor and found this to be true? I think the Guard is basically the same thing as the newer Banshee. And what makes these "braces" non NFA since they sure look like a stock? Seems like the ATF could easily change their mind on this but I guess the brace could always be removed if they did that.
 
While I haven't tried the CMMG version... I can say I cut down on bark and blast from the ejection port substantially ( In my 16" Colt pattern 9x19 PCC ) by using a 7.5oz 'ish buffer weight and a Tubbs .308 Flatwire recoil spring ( in a carbine length buffer tube )

The difference between the OEM setup and the "heavy 7.5oz and Tubbs" is dramatic. Much more Winnie the Pooh v. the OEM Linda Blair from the Exorcist.

I tried all the way up to a 10oz buffer and a orange ( ? ) Sprinco ... and while the blowback still functioned 100%, the recoil impulse moved toward the muzzle from the excess mass / spring weight slamming closed.

Enough momentuem from the 10oz etc, that it caused noticeable muzzle dip.
 
The CMMG is a delayed blowback and some have reported some improvements while suppressed. The braced may one day be challenged but they exist to assist those with disabilities and anyone will have a hard time selling that down the creek. To your point, you could immediately remove the brace, it's still a pistol, or drop $200 on it and create an SBR. Stamps are coming back well under 60 days.
 
Thanks guys. I guess playing around with buffers and springs would have an effect too.

So the wait for an SBR is shorter than for a suppressor? I just got to pick up a suppressor today after an 11 month wait. I did the ATF paperwork through Silencer Shop where I bought the suppressor. So if I buy a SBR, would the place where I buy it usually help with the paperwork?
 
While SBRs are good, a pistol can be carried loaded & accesable in your vehicle, in most states provided you have your CCW permit. And then there is the form required to take SBRs across state lines.

OFG

Yes, if laziness = convenience I see your point :ROFLMAO: His question was regarding the future of "the brace" and it is certainly in question. That, would render most of these pistols....fucking worthless. YMMV :LOL:
 
Thanks guys. I guess playing around with buffers and springs would have an effect too.

So the wait for an SBR is shorter than for a suppressor? I just got to pick up a suppressor today after an 11 month wait. I did the ATF paperwork through Silencer Shop where I bought the suppressor. So if I buy a SBR, would the place where I buy it usually help with the paperwork?

Yes....and yes. Most (eForm 1's) are clearing in 30-60 days right now. That's good. I remember the 30 days or less and that was great. I also remember waiting 9 months. It's a good time to SBR a pistol if that is your intent. Any dealer can help you with this process. Suppressors, on the other hand (Form 4), are still taking quite a while to clear.
 
Yes, if laziness = convenience I see your point :ROFLMAO: His question was regarding the future of "the brace" and it is certainly in question. That, would render most of these pistols....fucking worthless. YMMV :LOL:
Where do you get laziness? Have done the SBR state line forms many times. The biggest advantage to me is being able to have a loaded PISTOL in my vehicle.

Have put crutch tips on my AR pistol buffer tubes and they shoot very well with a good cheek weld. So no, loosing braces is not going to make my AR pistols worthless.

OFG
 
Where do you get laziness? Have done the SBR state line forms many times. The biggest advantage to me is being able to have a loaded PISTOL in my vehicle.

Have put crutch tips on my AR pistol buffer tubes and they shoot very well with a good cheek weld. So no, loosing braces is not going to make my AR pistols worthless.

OFG
:LOL::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO:

I understand your point, but by the time you cheek weld your AR pistol, via buffer tube, some crack head will have put 4 rounds in you with his Glock 19. The AR15 style pistols are great...when you have 3 points of rifle contact, but when you can't really make that happen the standard side arm becomes a much better option.
 
The CMMG is a delayed blowback and some have reported some improvements while suppressed. The braced may one day be challenged but they exist to assist those with disabilities and anyone will have a hard time selling that down the creek. To your point, you could immediately remove the brace, it's still a pistol, or drop $200 on it and create an SBR. Stamps are coming back well under 60 days.
First post here, but I’m about to build another AR. I was gonna do it as a pistol but your comment on sbr’s taking less than 60 days to clear has me intrigued. Is this for individual forms or trust forms?
 
As long as you e-file with ATF eForms, e-form one with your individual application, or trust uploaded as a soft copy, followed up by mailing your fingerprints in, will register your pistol in as little as 13 days right now. This is a great time to SBR and nobody can say how this process may be impacted in the future. Eforms is simple to use, payment is made on the the same site, and I've not spend more than 10-minutes during each submission with most of that verifying the information to ensure it's not kicked back. Easy to be a "stamp collector" right now!
 
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Does anyone happen to know if the Geissele AR 15 action rod fits the 9mm chamber? I’m looking at getting the 300, and want to swap the flash hider that comes with it. Wasn’t sure if there was some unique pattern or not being 9mm.
 
Does anyone happen to know if the Geissele AR 15 action rod fits the 9mm chamber? I’m looking at getting the 300, and want to swap the flash hider that comes with it. Wasn’t sure if there was some unique pattern or not being 9mm.

Yes, the Geissele reaction rod will work just fine with the CMMG Guard 9. I used mine reaction rod to swap handguards and muzzle devices on mine.
 
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