Reading this thread made me curious. So I measured some case capacities using demineralized water. I didn't have 8x57 and 7x57 that were the same brand so the results don't mean much but are still interesting. I guess if you're looking for small gains in case capacity, case brand might be the place to look instead of changing case shape.
Winchester 8x57mm = 60.8 grains
Remington 7x57mm = 56.6 grains
Privi 7x57mm = 60.3 grains
Measured on Ohaus explorer Pro E2102C


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