My Brown and Sharps keep batteries for months.
They have been in use for 18 years now, and still pass annual calibration specs.
My Brown and Sharps keep batteries for months.
They have been in use for 18 years now, and still pass annual calibration specs.
The simple answer is to use what you either have, are comfortable with or can afford. I have good Mitutoyo dial calipers and a set of cheapo Horrible Fright digitals. Both work well enough for loading ammo.
My 8" Mitutoyos are well past 20 years and will go for a couple of years if I turn them off when finished, I use them all the dang time and usually don't remember, but I never seem to need a battery for at least a year.
I use calipers and mics all the time. I learned how to use them when I was in R&D, now I use them for my engine builds. I would actually suggest a set of mics over calipers for measuring cartriges and the like. Calipers can be tricky to get repeatable measurements on curved surfaces. A micrometer, however will work very well for this. Calipers will work, but I think mics would be better. For reference, the accuracy of the chinese digital calipers is spot on. I have checked mine with the standards for my mics. I have a starrett dial caliper, the $20 digital set is just as accurate. Would I build a space shuttle with $20 digital mic measurements? no, but I think it will be fine for measuring tolerances for engine building and ammunition.
The cheapo digital calipers work well. I recently checked the accuracy of mine against the diameters of several U.S. coins and found the measurements to be within +/- 0.003"
