Re: Redding~ Competition or "S" type dies ???
With the bushing dies there is nothing to size the inside of the necks, and no need to. They rely on the necks being a uniform thickness, you will probably have to "trim" (can't think of the exact term at the moment) the necks to a uniform thickness, they make tools for it.
The traditional style of sizing die oversizes the neck and them relies on the expanding button to open the neck back up to the desired size.