Resizing 17 Fireball to 17 Mach IV Problem

[Bixahsheesah]

I had no issues when using new brass but when I ran some once fired through the Redding body die it wouldn't chamber. The gun is a Cooper model 21. Any help is appreciated!

 

[wildcatter]

Is the die a 17 Mach IV FL? It would need to be if using Fireball brass fired in a 17 Fireball in order to fit a proper 17 Mach IV chamber.

 

[Bixahsheesah]

I'm not sure. It's marked "17 mach IV body n4"

 

[Bixahsheesah]

According to the instructions it is a full length resizing die

 

[wildcatter]

It is probably not FL sizing at the shoulder. Hear is why.

" The 17 Mach IV will chamber in the 17 Fireball but the 17 Fireball will not chamber in the 17 Mach IV. The fireball is wider at the shoulder by . 006". So the Mach IV dies will load both cartridges but will work the Fireball more when FL resizing and the Fireball will not size the Mach IV at the shoulder."

I think you will need to get a FL Mach IV die, that should make life good.

 

[wildcatter]

A body die usually is a bit fatter than the FL for the same caliber, at least my Reading body dies are. I only use mine to bump shoulders on brass fired in my guns.

 

[Bixahsheesah]

Gotcha. Thanks for the info, I'll try a FL die

 

[Bixahsheesah]

that did the trick, chambers just fine now. Thanks!