I've got something new in the hopper.
7.62x39 loaded with 180gr Rem PSP CorLokt.
I just loaded up three for a velocity check. If it's able to hit 2100 fps, it should expand out to 300 yards at 1633 fps remaining velocity.
Mostly just experimenting. I bought a box of 2000 180gr PSPCL from Midway about 20 years ago, on sale for $99.00. Curious how they might work in the x39.