I have a set of redding "S" Type bushing dies. for my 338 lapua. I am still in the process of getting my dies fire formed (Lapua Brass). so I have not used my bushing yet. Where I am confused is why is there an expander ball? If I put the bushing in isnt the expander which is a given diameter going to undo the work of my specifically chosen Bushing? Maybe I am missing something?? Seems to me like the die would be better suited for a decapping rod that does not have an expander ball. can someone give me a hand with this?