Just got done putting a gas piston upper together for 7.62X39, had an old CMMG carbine kit that I had put on a 300blk and took off due to not working with subs. Barrel is a tactical firearms melonited Hbar,bolt is a Tactical Ambush NiB and carrier is CMMG Nib. So far I have on fired three strings of 5 rounds and rapid fire no aimed, then between each string took it all apart and inspect for problems. None yet but will do more testing latter this week.
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Nice. I ran the same CMMG kit with 7.62x39 a few years back and it ran flawlessly. Too bad the 7.62x39 mags were not perfected yet. The CMMG kits are some of the best kits out there but not very well know. I have their updated kit now and it runs 5.56 non-stop.

This 7.62x39 looks badass.

7.62x39 PDW

Well I have a total of 90 rounds thru it with one hic up, change out the buffer spring and buffer and has worked like a champ!
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