I use any 7.62/54 case I can find. They are getting kind of hard to come by.
Most of the ones I have are Grafs store brand or Prvi.
I shoot mostly cast. The 155 gr 7.62x39 LEE bullet and 200 gr Lyman.
18 to 20 gr of 2400 gives excellent loads for cast. Start at 17 and work up from there.
For Jacketed plinkers. I use pulled 124 gr fmj ahead of 49 or 50 gr of WC844 (H-335)
These shoot the best out of my M44 carbine.
The surplus stuff makes it look like a fire breathing dragon. kicks like one too.
My hand loads are much more shoulder saving.