Bullet setback. I'm stuck

[Sarrsipius]

Sir, the resizing die is the die that the rest of the dies on a progressive work around. For a pistol cartridge like the 9mm, the press must make firm contact with the bottom of this die.

A light touch as you described is not optimal. Screw this die down until it firmly stops the upward movement of the shell carrier. And be sure that all slack is completely removed from the linkage when the shell carrier is stopped.

Then adjust the other dies off this baseline. You might not be fully resizing your cases by allowing slack in the mechanism.

A 9mm reloaded cartridge should have a bell shape as should all reloaded pistol cartridges. Mixed headstamps have never changed any of this for me.

That is where I would start before I get too discouraged.

(BTW. .002 to .012 setback is not worth worrying about)

I'll take another look at it tonight. I believe it is contacting the shell plate. Do you know of any reference that would show what a dangerous amount of setback would be? I've read that the pressure increase caused by bullet setback is exponential and that you can go from "nothing to worry about" to "dangerous" in a very small amount of setback. I just don't know how small that amount is.

 

[mssmith44]

For the tightest die for 9mm try the lee u die. 1 mil under size. should make a difference for you.