The posting by Jim Watson is I'm sure an typing error on his part as the gun powders of the mid to late 1880's were finer in size and not coarser as he posted.
Actually, I was going by reports from people who have pulled bullets from old factory BP cartridges. They described relatively coarse powder.
You are saying it is the other way around? What calibers have you examined?
There is one gunzine author who decrees that the .45 Colt was never ever loaded with the rated 40 grains. Says him. I don't consider CotW to be a primary source for the 40 grain number, but Ed Ezell agrees at 40 grains, even if he did metricate everything and call it 2.6 grams.