I just turned a bunch of brand new RP .30/06 brass into 7x57. It is as simple as running it into your 7x57 sizing die, then shortening the necks with a small pipe cutter, resize them again, then trimming to size. Chamfer inside and outside the case mouth. Done.
(No tricks other than don't get lube on the neck or shoulder (but obviously lube inside the case neck) or you will get wrinkles.)

The case mouth thickness is a little thinner than PPU 7mm Mauser brass. They work fine.

Last edited by CarlsenHighway; 04/01/21.
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