If that photo is showing a fired case on the left, I have to tell you
it was fired in a completely normal .30/40 Krag chamber. There's nothing "improved" about it. Cases for rimmed cartridges are normally made with significant clearance at forward body and at shoulder. You can reload that case perfectly with standard .30/40 dies.
(You need to Login to view media files and links)Class86act wrote on Mar 2
nd, 2017 at 7:48pm:
I bought 100 unprimed new cases, so those will have to be resized, Amy more info on using 308 dies? I'd save a bit of money that way.
As FredC says, there's no need to size your new cases. Just load to normal pressure and fire.
Use .308 Win. sizer as you would a normal neck sizer, adjusting die body up or down in press to size neck only as far as bullet shank will be inserted.
If neck-sized cases eventually expand enough to inhibit easy chambering, .308 (or standard .30/40) sizer die can serve to bump back shoulder a bit and restore smooth chambering.
FYI, here's a drawing of the A.I. cartridge. Note the forward body and shoulder dimensions.
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