One thing which needs to borne in mind a "Dram" is a weight measure @ 1/16oz. While true Black Powder was more often dispensed by volume rather than wt, most folks then didn't have a sensitive enough scale to weigh charges. Even today we will set a powder measure's volume to drop a given Weight of the desired powder. If a rifle maker specified a 5 dram charg of a given powder & then supplied a fixed measure for that charge it would have been regulated to measure 5 drams weight of that powder, regardless of the volume it came out. Weight of a given volume of black powder can vary according to granulation & actual components used, in particular the charcoal. Thus any volume measure unless used with the powder lot of the powder for which it was regulated, will always be a compromise to some extent.
