Two Micrometers Don't Agree
I hope there are several machinists here that might know what I can do about the problem in the title. I have two 0-1" micrometers, a Brown & Sharpe and a Schure-Tumico(sp?) that differ when checking against a .310 plug guage. Both zero out when closed on the anvil but differ by .0004 when I measure the plug guage. The B&S measures exactly .3100. The Schure-Tumico measures .3096. Both have a vernier for the 4th place. I have cleaned both measuring surfaces but don't know what else to do.
1. Is there any adjustment that would make both measure the same?
2. Is that difference meaningful in reloading/casting?