That is true. I wondered why you said in a previous post that you would be bringing your powder scale to the range and weighing your powder charges! Didn't you receive a manual with your muzzleloader that explains the basics of muzzleloading?
There was confusion that both volume and weight used the same term. If it said milliters, I would have understood we were talking volume. If the sentence had said something like "150 grains by volume", I may have caught on sooner.
The rifle is still in its box. I won't have time to take it to the range until mid-March. My priority still is a fairly long honey-do list that built up during last hunting season. The list goes on for 2 single-spaced pages. I am only a quarter of the way through the first page and I am doing the easy stuff.
BTW If the unit of measure was minims instead of grains, I may have understood. (1 minim=1 grain, 15 minims=15 grains=1 cc.
10 cubic centimeters = 150 grains.