Use of expander ball on Redding S Type Bushing dies

[blt65]

I have been using my Redding S Type Bushing dies with the Expander ball. After some thinking and research I have realized that the expander ball is ruining my perfect sized neck when I pull it back through the neck of the case. Should I use the expander ball? I am using a bolt rifle and my bushing is .289 when my loaded bullet is .291. Thanks for your advice.

[kelbro]

One way to tell, test it. I upgraded my dies to the carbide expander ball. One die does better with it, one does better without it.

I think that it may be related to how much you are moving the neck ID. If your bushing swages the brass down to where the ball only stretchs it .001 larger, I doubt that it's going to disrupt your concentricity. If however, it's sizing .003-.005 (not uncommon with factory chambers) then it could cause issues. If that's the case, that effect can be lessened by using a larger bushing for the first swage and then step down to a smaller bushing for a final swage.

Neck thickness can also play a part so you could see a difference between brass brands using the same set of dies. The good thing is that the dies is easily tuned.