Sizing Button - Why do I need one?

[lester]

Could someone please tell me why I need to use a sizing button in my dies?

I'm comparing Redding's Competition dies that don't use a sizing button and the next step down their Type S dies that do.
I thought they were the same dies only without the micrometer on top. What's the sense in using a bushing with the Type S dies if your going to pull the sizing button through the neck?

I don't understand the need for the button in the first place. Is it because the neck wall thickness varies from different lots of cases? So if I don't use the button should I be turning all my necks first? Doesn't the button hurt the alignment of the neck?

 

[Ballistic64]

Most people lose the sizing button with the S type die.Also the S dies dont use a floating sleeve as the comp dies do.

 

[Mysticplayer]

You don't if you use a die that you can adjust to account for your neck thickness.

The expander ball was a simple solution for mass production of dies to account for varying brass specs. Simple but crude and can cause runout problems.

Today, you have two alternatives. The Lee collet neck die and the Redding/Wilson/hornday/custom die that uses bushings to size the required amount.

Jerry