I bought a 20 round box of loaded 30-40 ammo at a gun show a few years ago.  The brass was marked Western 29.  They were in a brown cardboard military box that was in bad shape. It was loaded with 220 grain round nose FMJ bullets.  I pulled the bullets and fired the primers off.  Very weak primers, made very little noise when I fired them.  I have reloaded the brass a few times with low pressure cast bullet loads.  My brass takes a standard large rifle primer and the brass is holding up well.

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