For one tip would be to lube every case the same and lube the inside of the necks equally too. If you don't lube the neck id you can pull the shoulder forward pulling the expander back thru the neck. --Quoted from first post or so.
That really happens. Lube the inside of necks and the expander ball.
Get a Wilson case gage and check each case after sizing. Wilson case gages are just miniture/portable chambers. They check over all length and shoulder.