Use the weights from the grain cart scale.    Even with all of the adjustments (moisture, TW and pack) measuring volume is a terrible way to determine saleable bushels in a bin.


That said, what is your goal of measuring the bins?       If its for crop insurance, just have them come out and do the measuring/calculating.

Pack factor gets fairly complicated as the pack factor continually gets greater with added depth, moisture and TW come into the pack factor calculation itself as well.