Best length barrel for 7.62x39?

[SethB]

I don't know where the idea that you need a full twist to stabilize a bullet comes from.

.45 ACP and .22 LR both use a 1:16 twist, but I use them in five inch barrels all the time.

ETA: I would use 16 inches for hunting and 12 for fighting.

[constructor]

We run 16" with a mid gas system, it allows the pressure to drop so the steel cases aren't stuck to the chamber walls when the extractor starts pulling them from the chamber. As long as they aren't over-gassed it shouldn't be a problem but, many are over-gassed.

[LMTRocks]

Is this ammunition corrosive? I am intrigued at the idea of a 7.62x39 AR, but have concerns about damage to the gas system (and other internals) when using foreign milsurp ammunition.

Thanks,
mbogo

After shooting this stuff since about march and taking the 16" upper apart I can attest to no gas system issues. The bolt does get a little "red" from the corrosive primers but that is quickly solved with Gun Scrubber and a brush after some range time. I also use it when I just want some blasting fun with my AR pistol. Both barrels look very good for the amount of shooting I've done with them this year. Just don't let the BCG stay dirty for a long time. Always hit it with some Gun Scrubber before you leave the range or go to bed.

[308sako]

Colt 16" shoots 165's at 2,000, 155's at 2150, 125's at 2350. Kills deer DRT

[OhThatGuy]

So an AK in 7.62X39 with a 14.5" rifled barrel and pinned muzzle brake will have nearly the same velocity as a 16" barrel? That is good stuff.