7.62x39 AR Pistol Help??

[thunter850]

I am currently looking for a backpack gun. I already have a lot of 7.62x39 and I think this might make sense coming out of a 7.5" or 8" barrel instead of 5.56. I also already have 7.62x39 AR Stoner "AR" style mags. I am wondering if these two components would work together or if the AR buffer spring would need to be changed to something else if the ar pistol lower has a 7.62x39 upper on it.

PSA KS-47 8" Upper: https://palmettostatearmory.com/psa...e-7-lightweight-m-lok-upper-with-bcg-ch2.html

PSA AR15 Complete Stealth Lower: https://palmettostatearmory.com/psa-ar15-complete-stealth-moe-ept-sba3-lower-black2.html

If i do need a different buffer spring, what do I need?
I see that PSA is making a 7.62x39 KS-47 now and Maxim Defense also makes a cool PDW in that caliber. Any recommendations appreciated.

 

[Rebel_Rider1969]

H2 or h3 buffer, same spring. Be prepared for the Muzzle blast. Linear comps are helpful.

 

[thunter850]

Do you recommend 5.56 or 7.62 at this length? Is 7.62 any better or worse than 5.56?

 

[Rebel_Rider1969]

Do you recommend 5.56 or 7.62 at this length? Is 7.62 any better or worse than 5.56?

No they both rattle teeth. I prefer the x39.

 

[Rebel_Rider1969]

No they both rattle teeth. I prefer the x39.

Both " can be" gas fussy in the short barrels. 7.5.
Worth considering folding..10mm.

 

[Murfpcola]

In the description on the upper you linked it says it will not work with standard ar-15 lower. It is for the ks-47 lowers that use AK mags. I think so anyways


EDIT EDIT. There are 7.62x39 pistol uppers that do use a standard lower. I have a 16” upper I bought from Sanders Armory that I really like. It is shockingly accurate with standard steel case ammo

 

[Jdcujo]

In the description on the upper you linked it says it will not work with standard ar-15 lower. It is for the ks-47 lowers that use AK mags. I think so anyways

KS-47 G2 upper will not work with a standard AR-15 lower.

Your spot on. That's from the description for that upper.
I will say I like my ks47 but it will basically only function correctly with magpul ak mags.

 

[850guns]

I also prefer x39 in the shorter barrels over 5.56. Some x39 bcg may need an enhanced firing pins and/or modified extractors to be 100%.
I traded my shorter 5.56 barrels and have gone to 10.5 and 12.5. Very little testing on either, but I was having issues with the factory built (BRO)10.5. (GRRR!) But it was kinda dry, oops, but was still problematic after a light lube. Who knows, I probably shot 15 or so and put it up...

 

[Jdcujo]

I've been lucky (knock on wood) with my 10.5 and 12.5 ar pistols. But mainly gotten to where sticking to the 12.5" . It got to where it was a question of how much performance vs maneuverability vs outright fecking noise.