What B.L.E. said.
I look at the brass shells like an ordinary muzzle loading shotgun. Whatever gives you the best pattern and energy is what you stick with (within reason of course). Some find that 1/2 inch of fiber wad works for them and some swear by just using a nitro card between powder and shot. I use 2 lubed felt wads (1/4" total) between powder and shot. Seems to give the best results for my 10 gauge muzzle stuffer.
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