CMMG 12.5" .308 Barrel

98Z5V · January 25, 2015

LOL...to paraphrase Miles Davis, "I got 'yer rules hangin..."

There's another quote out there, for you...

"Buy once, cry once..."

This isn't a cheap hobby, not in the least. Not saying you should look for the most expensive stuff, either. Informing youthat even some mundane parts for this platform can be expensive. Doesn't matter how loquacious you are about it, it doesn't change that...

Microgunner · January 25, 2015

Whoop, there it is.

Robocop1051 · January 25, 2015

12710061ec1b8ec6b7fa09807a2b4f6c7c208950

edgecrusher · January 25, 2015

Mine will be DI. I don't think piston driven rifles make that big of a difference unless you're shooting full auto or suppressed.

392heminut · January 25, 2015

Bwaaaahaaahaaahaha! <laughs>

Dane Armory · January 25, 2015

CMMG and POF should not be used in the same sentence. Pinto vs a Cadillac comparison.

CMMG has had a lot of bad quality issues on the 300Black barrels as of late so I would steer clear for a while.

survivalshop · January 26, 2015

This is a Pistol build right , I can see why you would you want a Match Barrel, but how far do you plan on shooting this Pistol ?

A good shooting barrel at half the price , in 308 , at extended pistol ranges , would work just fine . ( unless to take your Sig brace & put it up to your shoulder , which you would be committing a Felony doing , unless you had an SBR stamp <dontknow> )

I really don't know what people expect out of a Pistol build AR or what can be accomplished with them . I have never been interested in building one , myself .

liber · January 26, 2015

CMMG and POF should not be used in the same sentence. Pinto vs a Cadillac comparison.
CMMG has had a lot of bad quality issues on the 300Black barrels as of late so I would steer clear for a while.

Agreed, I didn't mean to do that.

I don't think I can afford POF, just using it as an example.

This is a Pistol build right , I can see why you would you want a Match Barrel, but how far do you plan on shooting this Pistol ?

Yes, this is a pistol and I will shoot mostly at 200 yards.

However, no harm in making the pistol to begin with, otherwise I can't put a shorter than 16" barrel on it.

Unfortunately I'm in California, so no stamp. :(

I'll take your sig brace comments tongue in cheek, as nothing has gone to court. Not saying it's legal, but even though the ATF changed their statement, that has not been proven yet in court and it's not known if it will even stand up.

I really don't know what people expect out of a Pistol build AR or what can be accomplished with them . I have never been interested in building one , myself .

You won't be the first person to make that type of comment. Here's my logic. Plenty of people shooting these at 200 yards, and the .308 is an accurate, and since I will most likely shoot this almost all the time at 200, I think it will be a fun firearm to own. I can use it with a sling, I can use it with a brace, I can use it with a Thordsen buffer tube cover. I can also reconfigure it to a rifle and put a longer barrel on it, at which point I could attach a stock legally. At least in the sense that with a barrel 16" or longer it no longer falls under the NFA SBR law.

I suspect though, with a 12.5" barrel, a .308 could be pretty good out to 400-500 yards safely. I don't think I will shoot this any farther than that. I'll be lucky if I can try it at that range.

I don't think a pistol will be any less fun to shoot than a rifle at 200 yards. <dontknow>

Matt.Cross · January 26, 2015

I can use it with a sling, I can use it with a brace, I can use it with a Thordsen buffer tube cover. I can also reconfigure it to a rifle and put a longer barrel on it, at which point I could attach a stock legally.

Microgunner · January 26, 2015

oh yeah, that does read like Dr Suess.

FaRKle! · January 26, 2015

This is a Pistol build right , I can see why you would you want a Match Barrel, but how far do you plan on shooting this Pistol ?
A good shooting barrel at half the price , in 308 , at extended pistol ranges , would work just fine . ( unless to take your Sig brace & put it up to your shoulder , which you would be committing a Felony doing , unless you had an SBR stamp <dontknow> )

I really don't know what people expect out of a Pistol build AR or what can be accomplished with them . I have never been interested in building one , myself .

Shorter barrels can still reach out plenty far. There's a great misconception that AR pistols are only good for short range.

Edited January 26, 2015 by FaRKle!

98Z5V · January 26, 2015

Shorter barrels can still reach out plenty far. There's a great misconception that AR pistols are only good for short range.

Not for 5.56, and the design of the cartridge, which is where this is all coming from. That 5,56 projo needs to fragment to do what it was designed to do - otherwise, it leaves a small entry wound and a small exit wound, straight through. Fragmentation ability is directly tied to bullet speed on impact. The speed reduction of 5.56 from a 11.5" barrel down to a 10.5" barrel is the major jump, and the major loss in speed. You're already at a disadvantage shorter than 11.5", due to that drop in speed at anything under that point/length.

Now, with those reduced speeds, and when you drop under the "fragmentation speed," you need to determine what ranges you'll expect to engage targets with said short-barreled weapon. If your job is room clearing, you can do that with a pretty short barrel, and that 5.56 bullet will probably fragment in that distance. If you're taking your 7.5" 5.56 pistol out to a 300-yard engagement point, that 5.56 projo is not going to fragment at that range. You better make a vital hit with it.

Anyway, that's the background on it. More can be found in the works of Doc Roberts, and his analysis and presentations.

98Z5V · January 26, 2015

For the record, I'm building a .308 AR with a 13.7" barrel, currently...

survivalshop · January 26, 2015

I see the advantages of a high powered cartridge with large capacity magazine in CQB ( room clearing ), but how you shoot at 200 yards with a brace or sling , with out a shoulder/cheek weld , to me ,doesn't seem like this would be very effective . No doubt the cartridge will make it that far & beyond .

shibiwan · January 26, 2015

Relax. 'Tis just a barrel. Nothing to lose sleep over. Besides, it's a 12"... somehow (IMO) that doesn't justify spending $$$$$$$$ on an expensive barrel for a short-range plinker.