The Dragunov does have some similarities to the AK. Being a gas stroke semi or full auto feed rifle. It is far superior though because it has a fully machined receiver (vs. stamped sheet metal) and three locking lugs (instead of two) and a shorter gas stroke and tighter tolerances. And of course the calibers are different. I’d love to have one but I don’t know why. I don’t shoot the guns I do have.
The nice thing about 7.62x39 ammo is that it sends a relatively heavy projectile out of the barrel at around 2350 FPS. This means that you do not need the projectile to be jacketed. Any alloy of lead which can be hardened by dropping your freshly cast bullets from the mold into water can be used. Old tire weights are often ideal, but you can add a small amount of antimony if you cannot find them. I often heat treat to get the best results. You can use a cheap hardness detector to verify your results. Properly made cast lead bullets do not tend to leave a problematic amount of lead deposits in the barrel with regular cleaning.
The brass is typically capable of being used several times so your largest expense is usually primers and powder. 7.62x39 is a very economical cartridge for those who cast their own bullets and reload their own cartridges.