M-52 Czech in an AR-15, why hasn't anybody tried it?

[Vaarok]

The AR-15 fires 5.56x45. AR-15 uppers are available in 7.62x39. Why hasn't anybody ever tried reaming out a 7.62x39 chamber to 7.62x45 Czech?

I have a Vz-52 (well, several, actually) and I find the M-52 to be a very potent and favorable round. Maybe it's just another damned intermediate cartridge, but the ballistics are flatter than the M-43 and given the size, I was curious why the hell not.

Hell, when I look at the prices of 6.8 SPC, 6.5 MPC, and all the other oddballs, it makes me wonder. Plus, it's a thirty-cal rifle round out of an AR without spending a thousand on a -10.

 

[HorseSoldier]

Will the overall length of the cartridge work with an AR-15 magwell/lower?

My guess would be it's either that consideration, or simply that the round is relatively obscure.

If you run a search, the Czech round is the basis for the "ideal intermediate" round proposed by Gary Roberts and others if we give up the M16/M4 mag well restrictions on OAL. Their round is, essentially, a necked down 7.62x45 (in 7mm), if I remember right, and has seen some experimental use in a rechambered Czech MG and maybe some other platforms, so it's not strictly a paper exercise and such.

 

[RockyMtnTactical]

Will the overall length of the cartridge work with an AR-15 magwell/lower?

That is possibly your number one problem right there...

 

[strat81]

Because I have never seen 7.62x45 Czech ammo for sale.

Maybe I'm not looking hard enough? How much does it cost per box?

 

[armoredman]

I have seen maybe 5 boxes for sale, covered in dust at one shop years ago. I know next to nothing about it, except CZ-UB said the rifle that the round was made for was poorly designed.

 

[Vaarok]

Czech surplus is unavailable, you just make it out of .220 Swift, and it's becoming fairly popular among people who've tried it. The Vz-52 is an excellent rifle, just most of the examples imported into the states came from somewhere in South America after extended use and poor maintainence.