The present case for the 7.92 x 57 mm ( 8mm) is the same as the one introduced in the 1888 Mauser.. So despite a .005 reduction in bullet diameter, I maintain the 8 x 57 predates the 7 x 57 by 4 years, and that the 7 x 57 was based on the 8 x 57..
Not that it's worth getting into a pissing contest over...

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