CCMG 9mm AR ammo issues

[Laxguy59]

Stop.
Before you start down the road of chambers and the like, check the simple stuff first.
I have a couple 9mm AR's built on CMMG lowers and have had several of these types of issues.
The FIRST thing I would look at is the buffer. What weight and size buffer are you using? I believe the CMMG comes with a 5.5oz buffer.
Some people use about $1.75 in quarters at the back of the buffer tube in order to shorten the stroke of the buffer.
What I opted for is an ultra-heavy buffer that resolves both weight AND stroke issues.

Here's a decent link:
http://beta.ar15.com/archive/topic.html?b=3&f=15&t=402969

Here's what I bought (9mm Q-buffer):
http://www.heavybuffers.com/ar15carbine.html

The second thing I would look at are the magazines. I have heard that metalform is THE standard and has the best performance, but I went the cheaper route, and got machine-modified Uzi mags and they have been more reliable for me than any other option I've seen in my gun. If you are interested, PM me, I have some that you can at least try and if they work better for you, I can sell you a couple.

I think both of those issues are more about cycling reliability. It sound like he can't even chamber the rounds to fire.

 

[bluesman2a]

Any round longer than 1.135" seems to jam when feeding.

I think both of those issues are more about cycling reliability. It sound like he can't even chamber the rounds to fire.

Not what I got out of it at all. To me, I read that the round does not correctly strip out of the magazine and doesn't even make it into the chamber.

OP, if I'm correct here, I would propose also that it may not be OAL at all, but the fact that the Atlanta Arms ammo probably isn't using as much of a charge (slower cycling). Can you give us some more insight here?

 

[Laxguy59]

Not what I got out of it at all. To me, I read that the round does not correctly strip out of the magazine and doesn't even make it into the chamber.

OP, if I'm correct here, I would propose also that it may not be OAL at all, but the fact that the Atlanta Arms ammo probably isn't using as much of a charge (slower cycling). Can you give us some more insight here?

ah good catch.

 

[jba6511]

Correct, when striping the round from the magazine it does not correctly chamber and instead jams, causing dents and bends in the round. The gun is factory built from cmmg

 

[Laxguy59]

Correct, when striping the round from the magazine it does not correctly chamber and instead jams, causing dents and bends in the round. The gun is factory built from cmmg

well try those lcjwholesaler mags, they work perfectly in mine with all types of 147gr
http://shop.lcjwholesalestore.com/32-Round-9mm-Magazine-32-Round-9mm.htm

 

[bluesman2a]

Correct, when striping the round from the magazine it does not correctly chamber and instead jams, causing dents and bends in the round. The gun is factory built from cmmg

Yep, you described the issue I was seeing in mine exactly. dents or bends in the sidewall of the round. Another was pushing the bullet down to "neck" deeper in the casing.

Betcha it's a buffer.
If you want to play with it some, I'd be happy to meet you at a range on my side of town and let you try either my buffer(s), and/or mags. I get that it's a CMMG built gun, but I don't think they have a buffer that will solve this kind of problem on the shelf, this may wind up being an aftermarket solution... which would suck cause it's not generally cheap.

If you DO wind up going with a buffer, I also ordered a Wolf XPS spring for mine too, might try that as well.

 

[jba6511]

Thanks I sent an email to customer service so I will see what they say. I might take you up on your offer since you are not too far away.

 

[sovietak474u]

Yep, you described the issue I was seeing in mine exactly. dents or bends in the sidewall of the round. Another was pushing the bullet down to "neck" deeper in the casing.

Betcha it's a buffer.
If you want to play with it some, I'd be happy to meet you at a range on my side of town and let you try either my buffer(s), and/or mags. I get that it's a CMMG built gun, but I don't think they have a buffer that will solve this kind of problem on the shelf, this may wind up being an aftermarket solution... which would suck cause it's not generally cheap.

If you DO wind up going with a buffer, I also ordered a Wolf XPS spring for mine too, might try that as well.

Nice fella here, people like this individual is why I love the odt .

 

[bluesman2a]

Nice fella here, people like this individual is why I love the odt .

I'm just paying it forward. I didn't learn about AR's in a vacuum, had to do a lot of research and reading, but a lot of folks here and elsewhere helped me out.

Besides, 9mm AR's are just fun, but they aren't the same as your average beAR, lots of mis-information, not much real information, but you occasionally hit pockets. That's what I like to share.

 

[sovietak474u]

I'm just paying it forward. I didn't learn about AR's in a vacuum, had to do a lot of research and reading, but a lot of folks here and elsewhere helped me out.

Besides, 9mm AR's are just fun, but they aren't the same as your average beAR, lots of mis-information, not much real information, but you occasionally hit pockets. That's what I like to share.

I hear that. I've read horror stories about 9mm ar-15s. I took the plunge anyway and i love my 9mm ar. It has yet to have a malfunction.