I have a digital scale for charging small refrigeration units that are charge critical. It measures in the tenths of an ounce. I put the #30 bottle on the scale, drop the small bottle into ice water to chill and fill until the big bottle looses #1.
Weigh the little bottle again to be sure. If you have the gear it is easy.
Great! More gear to buy!
Thanks for the low down, CM
Stocks