Thanks for the responses everyone. So far I have used my dial callipers and verified case measurements in the Hornady Manual 9th Edition and aside from being a bit short all readings are within 0.001 inch so far. Wall thickness on the Imperial .308 casings is in the range of 0.012 to 0.015 inches and a check of 7mm-08 Remington casings yielded a consistent reading of 0.012 inch. Will load up 139 SST gr. test loads in RP 7mm-08 casings and test this week.