Weighing Homemade Black Powder....70-75%

I have shot My Homemade Black Powder exclusively in a .62 (20 gauge) Indian Trade Gun, Pedersoli Flintlock.
My Powder is Standard English Recipe of 75-15-10.
For a 70 grain powder charge I shoot a 100 grain volumetric measure.
I also shoot 100 grain by volume shot measure over the powder load. My wadding has been exclusively Hornets Nest Paper (sometime hard to get) My over shot card/wad has also been Hornets Nest Paper (Somewhat dense and fire retardant).
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