FrankenMauser,
Do you have a comment about my question of why bird shot should not be used in a ported revolver?
Loose shot can impact the edge of the porting and cause damage via impact, cause damage via 'bridging' (shot charge getting lodged in the barrel), clog the ports, or cause splattering,
Shot in shot capsules through a ported barrel... Without thorough testing and a high speed camera, I can't answer whether or not that would cause an issue.
Speer says the capsules shatter upon firing, but my limited amount of testing has provided no evidence either way.
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I use loose shot, fiber cushion wads, and nitro cards in an unported barrel. I have used styrofoam, cardboard, card stock, and several other 'DIY' options in the past, but commercially-produced wads are cheap and don't foul the bore like plasticized cardboard or styrofoam. For $20, I can get enough nitro cards and fiber wads to last me 40 years, at the rate that I use the .44 shot shells.
As you may have noticed in the photo above, I sometimes don't even use an over-shot card. Instead, I load the top of the shot charge with nail polish, and brush a little onto the case walls. After 2-3 coats, it's rock solid for handling and recoil. On paper, however, it has no affect on shot pattern. As such, I believe the nail polish shatters upon firing. As a bonus, the residue in the barrel and case get burned up, since nearly every ingredient is flammable and a primary ingredient is actually nitrocellulose.
