Hi Greg,
My scale isn't a high precision scale but it does measure in 0.5 gm increment. I have 5 outer tubes, 2 for daily precipitation catchment and 2 for replacement at 8:00 am, and the other for measuring new snow and total snow on the ground SWE. A couple are 8 years old and the most recent this fall from CoCoRaHS Canada. I got the scale before first snowfall in November and empty weighing for the 5 tubes at the time varied from 451.0 to 460.5 gm. I have continued to weigh the empty tubes after each rain and snowfall and have found that the same empty outer tube can weigh different on different days, with a +/- difference of up to 3 gm. I've only submitted the weight method SWE to CoCoRaHS for my weekly total snow on the ground where any difference is relative minor. I wait for the snow melting to submit the daily SWE.
A bigger beef is that I submit in metric and CoCoRaHS converts to Imperial in their records and then display back in metric and with the rounding then does not display nor log what I submitted - i.e. 0.6 mm becomes 0.5 mm and 26.0 mm becomes 25.9 mm, and in metric the increments are in .2s so 0.5 and 25.9 shouldn't exist.
Enjoy,
Paul