I have been relaoding jacketed bullets for over 15 years, however I have never loaded cast. For practice I would like to use gas-checked bullets with the same profile as my jacketed hunting bullets. I would like to shoot 250gr RNGC in my 358 Winchester at around 2300 fps. Will there be a problem with leading? Also, where can I get an expander die to flare the case mouth? Any help from you guys is much appreciated. Thanks.