Just to reinforce what others have already observed -- my BH weighed charges of 80 grains come to roughly the 110 grain by volume mark on the BH tubes, and 90 grains weighed comes in close to 120 grains on the tube markings. I've double checked this using two different scales, so clearly the error is from the tube markings. For consistency and confidence in charge levels, weighed charges would seem like the best way to go.
