Hmmm, last two times I had my Yugo out, it slam fired two rounds once each time. When I got it home last time, totally disassembled the stinking bolt assembly. Even ran pipe cleaners through the firing pin channel. Probably should get the firing pin spring mod, but times are tough right now. I wouldn't even be shooting if I didn't have a ton of ammo I already reloaded.
what are you reloading ? I loaded some of the surplus ammo for a while, till I had some primers work loose causing it to full auto fire. Now I only reload American brass.
Clean your bolt, especially around the firing pin. Most are caused by the firing pin not returning to the rear position. If need be a few places sell spring kits for the firing pin so it'll return automatically. You can also take the bolt apart and clean the pin entirely.
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