A few years ago I inherited a bunch of 12 gauge cast shotgun slugs, Foster type with no brace like Lee has in the hollow skirt of their mold, and I was wondering how much wadding goes into the skirt upon firing using fiber wads, what type are used, and how well do modern plastic wads work? When I load mine' balls or hollow base bullets in my black powder rifles I let the powder fill the vacant space as it will or will not when I seat the bullet. Using modern powders for the shotgun slug pretty much require wads and spacing fillers. My father reloaded his own, but I have none of his data. The mold is a Lyman 1 oz mold. I would appreciate any useful data. I have no fiber wads or over the powder nitro powder wads at this time, so whatever I decide upon will have to be purchased. I remember using over the nitro powder wads and fiber wads when we first started reloading shotgun shells back when I was a lad, and I think my father used the wads he still had after plastic wads became the norm. He hunted deer very successfully near Winterset in Iowa using his reloads.