Reloading brass hulls is distinctly different from the plastic ones.
For starters, the standard one-piece plastic wads don't fit. The brass walls are thinner than plastic, making the wads loose and causing powder to leak past them. Primers are also not the same as battery cup types used in plastic shells.
YES, the brass shells are intended for loading blackpowder loads with old fashioned cardboard wads, fibre wad column, and overshot card wad. The overshot wad is sealed in place with wax or "waterglass" resin. A light roll crimp to improve feeding reliability completes it.
You will find that the brass shells are much roomier than plastic shells with the base wad. The roominess is needed for the bulk fo BP loads measured in "drams". Exact weight is not nearly as important as seating without airspace.
I've experimented using smokeless powder in brass hulls, but with mostly unsatisfactory results, since the plastic components are simply not intended for use in brass shells. The closest I've come to using modern shotcups is to cut them down to fit in the brass shells. You will also find that the shot load must be firmly seated over the BP to burn properly.
