I have a dial caliper of an unknown make, I bought as used, 30+ yrs ago off the Snap On rep. I learned to read a micrometer about 57 yrs ago, probably a dial caliper too, dad had a machine shop. For reloading, all I want to know is am I hot or cold of the mark I am seeking to achieve, ie; base to datum, which fired case is the longest one on the first firing, how many are about how close to it, did the longest ones grow over the first measurement on the second firing, did the die move the shoulder or not. I use the micrometer to check base and shoulder dia changes, a ball mic to check neck wall thickness. Whatever length or dia I hit the first time is the mark I gauge from and I record them all, I can see if the needle or barrel markings moved from original one way or the other, that's all I want to know about it. I have pin gages I can double check them with as a gauge to check basic accuracy. And I don't have to worry if the battery is good or not, or if a chip is assigning proper values. I just find I have less doubts about a dial caliper or an old mechanical mic.









