I shoot Swiss exclusively.
Swiss and even Goex is far better powder than almost anything made in the 18th c. Though powder used by the military was much more carefully controlled as to the ingredients. In high humidity a powder made with less than pure saltpeter will collect moisture from the air and effect its burn rate. If the ingredients are bad enough it can be unusable. Sailing for 3-4 months at sea and then having the powder not perform? The British would not accept powder coated with "black lead" Graphite. Most of the powder made in the 18th c was stamp mill powder and was often not even pressed and broken but pressed through a screen, by hand, in its damp state to make "grains". The great advance in powder making was in abandoning the stamp mills and using wheel mills and pressing the powder into cakes and then breaking it into granules. Pressing gave uniform density when done right which helped control he burn rate and made the powder more consistent if pressed uniformly.
The European powders, at last report, are made with much better charcoal. This is also important. Charcoal is the fuel and how its "burned" and what wood is used can have a great effect on the powder velocity production, fouling and shot to shot variation.
Now...
I have a 67 caliber rifle patterned after a English rifle circa 1810-1820. It has a Nock breech. If I shoot low grade powder it simply becomes unworkable. I have even had problems with Schuetzen. The problem is that a powder that produces flakes of fouling will drop a flake over the passage to the antechamber and powder will never be present at the vent. Required putting powder through the vent to get the rifle to fire. So I use Swiss. This tells me that by the 1780s (Nocks patent dates to the early 1780s would have to look up the exact year) the British must have had pretty good powder available to the landed gentry at least and by extension their military so far as the fouling characteristics.
How much such powder may or may not have been used in the Kentucky rifle Circa 1780 is only a guess.....
So almost any powder we use today is in someway or another, usually in the milling and the use of retort charcoal, is "better" than what would have been used by Morgan's Riflemen for example. I just know that lower grade powders can't be used with my Nock breech and likely would cause issues with either of these and if a flake blocks the vent any plain breech as well.
Dan
