reloading 7/8 oz crimp issues

So I have my, new to me, RCBS Grand and have set up all of the stations except the Crimp Start, Crimp and Final Crimp stations. I’ve checked my components: Remington (STS, Nitro/Clubs) 18gn Titewad powder, 7/8 oz shot, Purple Duster wads. Individually measured the powder and shot charges. I...