Let me apologise in advance, if this is a stupid question.
It is my understanding that while black powder is measured by volume, smokeless is measured by weight. If this is the case, is there some formula I can use to figure what charges of black powder to use if all I have is a regular smokeless powder scale? I guess what I mean is "what would 80 grains of FF by volume actually weigh on a scale"?
Like I said, this may be a stupid question, but I have to ask.
Thank you all

Both can be measured both ways. Certainly, a MEC reloader (for ex.) drops by volume-- Lee yellow powder dippers are designed for smokeless, and are naturally by volume.

Most of the time, BP (and 'subs') are measured by volume. For more consistency, you can measure using a BP powder measure-- weigh the volumetrically measured load, and duplicate the load by weight.

Randy,
I guess that I was not clear with my question. What I am trying to do is find a way to measure my black powder charges on a scale, without having to buy a volumetric powder measure. In order to get away from pelleted loads, I want to pre-weigh my charges of black powder before leaving to hunt or shoot.
So, is there a formula to convert gr. volume to gr. weight?

Yes, BUT it varies from brand to brand.

You are far better off buying a volumetric measure that costs less than a happy meal-- you'll save more than that on the first box of pellets that "you don't buy."

Gotcha!!!! Thanks. Priced one, and had no idea the were so cheap.