I am doing a project of shortening a 300WSM. Made a case forming die to set shoulder back .300. Reamed die allowing for .125 of shellholder. Retained Winchester's 35 degree shoulder.

Annealed Winchester cases using 550 degree Tempstick. Cases cases form easily. However They have partial axial wrinkle at the junction of body and shoulder. The wrinkle is small.

I tried forming unannealed brass and still get wrinkle but also some cases collapse at shoulder/body junction.

Any advice? Will fire forming take care of this?

Wally
wow@efn.org

Wally, I'm wondering about your case lube. Maybe you are using too much, not enough or maybe just getting it up where it don't belong considering what you're doing with the case?

Are you talking about what I call a "grease dent" like can occurr if you get too much grease up around the neck and shoulder? IF so, I don't believe these will fireform and go away totally.

The slickest lube I've found on the market today is the spray on lube. I use the RCBS variety but I think all of them use the same stuff in this mixture. I would say invest in a can of this, spray your cases good and let them sit a minute or so and then try a couple. See if that helps.

And I hope THIS helps.

It's likely the thickness of the brass in the old shoulder/body that is causing the wrinkle. Also, using a 550 degree Tempilstik doesn't give you annealed brass. Brass doesn't start changing until you get ABOVE 580 degrees. The best annealing temperature for case brass is between 680 and 700 degrees. You might try annealing to that temperature, or more, and see if the more ductile brass will form better.

I've had exactly that same result in forming 22-250 brass from military 30-06 and nothing I could do would eliminate the wrinkles. They are harmless but unsightly. In my case I found that using shorter brass, 308, and annealing before hand, did help but some of the cases still wrinkled. I concluded it was the thickness of the brass.