Oh Alexander,
It is true that 30 years of close studying have greatly added to my special knowledge; still I am afraid I'm not onmiscient.
1. There was certainly no 'average' powder measure for each charge. In older sources we read that that the earliest 14th century barrels were loaded almost up to the muzzle so that the ball could literally be seen. Some of the
Steinbüchsen of ca. 1400 which I recently posted, with their short actual barrels (
Flug) and rather long powder breeches, seem to suggest a barrel length of ca. 2-3 balls imagined to be placed one above the other. No sure aiming ...
2. We know very little, if any, about wadding. Presumably in the 14th and 15th centuries, there was little or no wadding at all and most probably consisted of wooden or hemp plugs. There are illustrative sources of ca. 1400 showing a small stone gun (Steinbüchse) standing upright while being loaded by two men, with the ball seen at the muzzle and plugged by wooden wedges hammered in. This would mean that early plugging of loads actually meant plugging or wadding the ball rather than the powder load.
3. Concluding from the calibers of the earliest preserved barrels (Loshult and Berne guns and others but NOT Tannenberg!) we may assume that in those days, the average caliber of a small handgun was about 3 to 4.5 cm - cf. my earliest small stone ball I posted a few weeks ago. In the course of the 15th century, it narrowed down to ca. 1.5 to 2.0 cm.
4. Following what I said in paragraph 2, I believe that both waddings of the powder measure and double waddings were not common to the 14th and 15th centuries. No felt or hemp waddings are known before the early 16th century; I do have some felt plugs in my collection but cannot date them any closer than '16th to 18th century'. I have never had the chance to extract a wadded loading of an original barrel earlier than the beginning of the 17th century, and that was felt plugging the powder measure and separating it from the lead ball which again was wadded by a bunch of hemp and in some times, printed paper. With the arrival of paper cartridges in the first half of the 16th century it became wide use to rip off the ball with the teeth, pour the measure of powder down the barrel, 'spit' the rolling ball right after it, crumble the paper and put it in the muzzle as a wadding and then just ram the whole load down with two or three stomps of the ramrod.
5. The actual load of powder I extracted from my 1481 haquebut barrel was not very much indeed, maybe 50 grams. I guess it was just the remnants of a bigger original load which, together with the missing ball, had fallen out long time ago. It would therefore be mere conjecture to make a section drawing.
You will see it all within a few weeks anyway, you lucky devil!
Best wishes,
Michael