Wanting a .45ACP AR completed carbine

[RustyKnifeUSMC]

Does anyone know if there are any manufacturers selling completed AR carbines for .45ACP that use Glock 21 mags?

I know that Quarter Circle 10 does uppers, but uppers only.

[CRAMBONE]

Quarter Circle 10 does make .45 Glock lowers.

[interfan]

I believe New Frontier Armory does as well. I think they had one in their retail store the last time I was in there.

[sidewaysil80]

Whats the concenus as far as blow-back vs gas? Is one more proven the other? More versatile?

[SteyrAUG]

Whats the concenus as far as blow-back vs gas? Is one more proven the other? More versatile?

I don't know what the consensus is, but gas is unnecessary for most pistol caliber carbines. Trying to think of one that even exists.

[NongShim]

I don't know what the consensus is, but gas is unnecessary for most pistol caliber carbines. Trying to think of one that even exists.

MPX is.

[SteyrAUG]

MPX is.

Didn't know that. Any reason why?

[Auto426]

Didn't know that. Any reason why?

My understanding is that the MPX was basically an offshoot of the MCX development, hence the operating system similarities. I think a large part of it was also that they thought they could after some of the LEO/MIL market with aging MP5's and a non-blowback system would give them a competitive edge over their mostly blowback competition.

[SteyrAUG]

My understanding is that the MPX was basically an offshoot of the MCX development, hence the operating system similarities. I think a large part of it was also that they thought they could after some of the LEO/MIL market with aging MP5's and a non-blowback system would give them a competitive edge over their mostly blowback competition.

Is it DI or piston? Trying to understand what a gas unlocking system offers that is superior to straight blowback. I understand the advantages of closed bolt vs. open bolt when it comes to such systems, and I get that the delayed roller HK systems gives the MP5 a very smooth cycle. But what is a DI or piston gas system going to bring to the table? Won't it just rocket the bolt carrier to the rear at Mach 4.3?

I know it's pistol calibers but still. Even HK went back to their simple blowback on the UMP and just decided to make it a closed bolt setup.

[call_me_ski]

It has the same tappet system of the MCX it is just right ahead of the chamber. Supposedly it is designed that way because a firearm that has a locking chamber will be quieter when fired suppressed vis-a-vis a blowback/delayed blowback gun.