First off, you need to know exactly what you're measuring. Here are the SAAMI cartridge and chamber specs for .30/06 -
Note the measurements from base of case and chamber (bolt face) to the .375" datum on the shoulder. Case = .2.0526" to 2.0456"; chamber min. 2.0487", max 2.0587". Since none of the dimensions you're quoting are within these specs, we have to conclude that either your measuring tool isn't providing an accurate