The normal shot load for a .410 is 1/2 oz. I guess you will have to measure out about 220 grains of fine shot, and see what measure it will fit in. The starting point for BP shotgun loads is a "square load", meaning; the same volume of shot and powder AND the shot or powder column is the same height as the diameter of the bore. Most people don't actually measure it that way. It is easier just to accept the normal or light load as a starting point. Often less powder than shot will give tighter patterns. I've never loaded a .410, but the loads are quite small as it is, I'd be tempted to stick with a square load, that is by using the same measure for shot or powder.
(Another indicator might be data for the .44-40, as a .410 was a wildcatted .44-40 made for wild west show shooting. .44-40s use 30 to 35 grains of black powder.)
19 Mar 07; Last night i did some cut 'n try. An old red LEE 141 dipper takes about 35 gr of GOEX, and about 215 grains of #8 shot. That is just a bit less than 1/2 oz. of #8 shot. (#9 would weigh a bit more, and would be a better choice.)
The load is built up as follows
1. pour powder into the primed shell
2. over powder wad ( a fairly hard card wad about 1/8 " thick
3. cushion wad up to 1/2" thick, sometimes containing some lubricant
4. shot
5. over shot card. a thin card. I use cardboard from a waxed milk carton punched out with a 11mm arch punch, or with a cut off belted magnum case. Ammo packaging or cereal box material works well.
6. Elmer's glue run around the overshot wad to seal it. The type of glue can vary depending on what you have. The original sealing was "waterglass" (Sodium silicate??) but most modern cheaper glues are good.
Try the net, Track of the wolf, Dixie gunworks, Circle Fly, etc. for proper wads.