Kassner 9mm??

Is it a BHP clone?

There's seems to be a family with that name who's had their hand on importing various firearms over the years including stuff from FEG in Hungary. I believe the president of Charles Daly is a Kassnar. I think Kassnar imports might have been the old man. Perhaps he'll come by and elaborate for us.

I actually don't think much of the Hungarian Hipowers. They are generally very good looking with some awesome bluing, but I've found the internals to be a little less than ideal (soft!). Others have reported similar experiences, having to replace lots of parts to get them working to their satisfaction. Others have reported having nothing but good service from their pistols. Go figure.

Double action or single action? Vent rib on slide?

If it is a FEG Model PJK-9HP, it is a very serviceable hand gun. I've had mine for more than 10 years and maybe 5000 rounds thru it, my loads with my cast bullet. Good gun, never a malfunction and mine uses Browning HP magazines, 13 round, I've got several.

I had one with a crack running right thru the 9mm stamping on the barrel.