Wildcatting questions....

[Carbon_15]

I have been kicking this idea around for years now, and I finaly have the disposable cash and a competent gunsmith to make it happen. I want to make my own custom caliber. I would like to take a 10mm and neck it down to .30 caliber and use 110 grain 30 carbine bullets and/or 30-to-22 Accelerator sabots. Kinda like a 7.62x25 magnum.
I dont have any idea where or how to start. My gunsmith can machine the barrel out of a .30 blank and cut the chamber by hand (he just did that with a LCP, turning it into .32NAA)...thats the easy part. Where do I come up with the dimensions? Which do I need first, custom brass, or custom dies? Where do I get those?
I know people do it all the time...It cant be TOO hard.
Thanks,
Jason

 

[Jim Watson]

I am not a wildcatter, but just to get things started...

The easy way would be to start with the reamers. Contact PT&G, Manson, or Clymer and tell them what you want, a 7.62x10mm Norma. They would probably walk you through the process. Buy a chamber reamer and a sizing die reamer. You could probably use the chamber reamer to cut a seating die, but ask.

Midway has die blanks.
http://www.midwayusa.com/ebrowse.ex...112&categorystring=9315***731***702***9339***

Ream one with the sizing die reamer and another with the chamber reamer (or a seating die reamer, if required.) Thread for decapping rod and seating plug, respectively. You can flare with a Lyman M die. Hmm, might have to make a taper crimp die, mightn't you?

Hopefully you could make some cases by running 10 mm brass through the seating, then the sizing die. If not, a 9x25 Dillon die might serve as an intermediate step without having to go to the expense of custom form dies.

Machine the barrel blank to fit the gun, chamber, load some of that brass and go shooting.