Notice that "cap and ball" is testing in a 10 bore SxS WR and is using 1.20(rounded) ounces of shot. I see that his shot in the measure is rounded, so likely a full 1 1/4 ounce of shot, but
only 70% of that (87gr. equivalence on his powder measure. Mathematically, I make that to be 60.9gr. powder. That is a light load, especially for a 10 bore. Interesting.
That was the first test. Second test was with 65gr. powder. That's only 2.38 drams. 2.5 would be 68 grains. This is a 10 bore.
When he went to almost 3 drams and the 1 1/4oz shot, he blew the pattern and hit heavy was holed the paper. The final load when using corn meal, was 70gr. 2F Swiss. That is a light load
for a 12 bore, let alone a 10 bore. I think, still using the 1 1/4oz. shot.
Interesting.
I do have to comment that 25 birds out of 35 thrown, is not very good shooting. Mikey B. can attest to that.