I was having a few problems with the 9mm and 8 bhn cast boolits also ...but
the answer was a NOE boolit mould , #358-124-TC GC , sized to .357" , lubed with soft Lithi-Bee lubricant , with a gas check attached and then the thing that helped the most ... expand the case mouth with the correct sized NOE Expander Plug , the ones with the correctly sized M-Die Expander profile ... and ( Voila' )...Wah Lah ...
Problems solved ... I honestly believe the gas check does a good job in the Pesky 9mm , if you wish to use softish boolits ... drive em fast and the soft slugs mushroom ... the GC protects the boolit base / barrel from leading .
Gary