Yeah, the 9mm is a PITA to deal with when using cast. It felt like a never ending struggle. Alloys, powders, decoppering and polishing bores, lubes, different molds, M dies, case swaging, partial case sizing, modifying neck sizing dies, etc.. it sucked! Turned out the cartridge case was swaging my boolits down to 0.355" and I was getting leading from blow by. A modified 38spl M die plug in my M die did the trick. All is well now.
I second the cast boolits forum. Good guys that dont mind helping you out.