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Piston is way better. For sure. Do it and cry once and be happy forever.

I would go to Bear Creek arsenal and they have an amazing one. If you are careful you can get it on sale for $239.

My Bear Creek arsenal 458 socom is so awesome!!!

The only other issue seems to be mags. 7.62x39 has a very aggressive case taper that wants a more aggressive mag curve, and the larger diameter of the round itself makes feeding out the front of a standard .223 mag problematic. Not that I have mags or rounds on hand to check before writing this post or anything. Pure speculation. ;)

Going with bear creek and their gen 2 enhanced 762x39 and their recommend mags? It works like a clock.

Well worth it.

Kak is another one.

A few manufacturers make them but then it's more.propriatary of a build if you don't know what's going on.

Yeah I'm regretting selling my custom dead nuts reliable build for $650 that was awesome upper.

The Zev is nicer but I do regret...