paul buchanan,
Machinists have worked in thousanths of an inch( or tenth of mm)ever since " before the Corps of Engineers issued the permit to dig the Chatahooche river".I understand John M Browning, himself, did his design work and thinking in fractions of inch, but he was not trained as a machinist( he made prototypes and someone else drew the patent drawings).BTY your friend's caliper is collectable itself,they are fine tools.To work consistently to a ten thousanth would almost require a precision grinder(we were talking old tools, not CDC).
Mike
Last edited by Der Ami; 02/10/15 09:45 AM.
