Making a custom wildcat chamber while avoiding the cost of a custom reamer is both possible and practical using a pair of standard SAAMI reamers you likely have in your shop, or can readily rent or borrow.

by Norman E. Johnson

As a sort of unconventional project, I set out to develop a special wildcat cartridge based on a commonly available parent case. I knew precisely what I wanted but didn’t want to go through blueprinting a special custom reamer in getting the job done. The cartridge I had in mind was based on the .243 Winchester Super Short Magnum case, necked up to a caliber .308 bore. I had a Broughton stainless target barrel with a 1:16 twist chambered for the much smaller .30BR which I would re-chamber. I also had a Weatherby .300 WM barrel with a 1:10 twist for the other chambering which I would cut down and rethread. The project has had a most favorable result and I named my new creation the .30BR Magnum.

Read more in our December 2014 issue. Back issues are available.

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