7.62x39 loses very little with each inch of bbl removed....and the supersonic ballistics are similar to 300 BLK on paper even in short bbls. In the real world, X39 hits steel a LOT harder than 300 BLK. I have XCRs in both x39 and 300 with 9.5" bbls.Everyone seems to want a short barrel 7.62x39.
If that's the case then switch to 300 Blackout.
It's designed for 8" - 10" barrels and packs a better punch than the 7.62x39. Also you get less flash out the muzzle, easier to suppressor, and is a much better choice.
As for the 7.62x39 I would recommend a 16" - 20" barrel so you burn all your powder and get less flash. A short barrel 7.62x39 is like a short barrel 5.56. These rounds are not designed for a short barrel and an AR is not really designed for those two in SB form.
However the 300 Blackout and a short barrel AR are a match made in heaven.
Absolutely. Add a good blast shield and gtg.Plus, 7.62x39 is significantly less expensive and more broadly available.
Old thread, but the information can still be of help to anyone else..ideal barrel length for 7.62x39