CJ,
Go to the top of the forum and look at the posting about cannon shooting safety and click on the two links in that posting. Those links will take you to sites that give you the formula for loads.
I have been looking for a site that tells how to make cartridges. Use be that the powder was put in plastic sandwich bag and then in heavy duty tin foil to maek cartridges. No loose powder.
Black powder is measured by volumn, put away the scales.