If you are speaking of a load of several 00 buck in a smoothbore pistol, I haven't tried that. I have done it with a 20 ga. smoothbore long gun, with pretty good results.
I have shot #5 and #6 birdshot in a 20 ga. Jackie Brown flintlock pistol, 8" barrel. I find that useable patterns can be had out to 10-12 yards, have killed a few squirrels in that range.
I usually load 30-35 gr. FFFg Goex and 35 grains equivalent of shot.
I fool around with different waddings a lot, so I've tried 2 hard card over powder and one thin overshot, 1 hard card+ a 1/2-inch lubricated cushion wad with a thin overshot, tow, both over powder and over shot, and shredded cedar bark the same. I don't find one particularly better than any other, patterns get pretty thin and uneven at 15 yards with all of them.
Pattern using tow, 10 yards:
Pattern using cedar bark, 10 yards:
And pattern using 2 hard cards, one thin overshot, 12-14 yards: :grin:
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