check out this link:
http://www.chuckhawks.com/muzzleloader_shotguns.htm

If it is a rocklock don't use any black powder substitute like Proydex only use real black powder. For the main charge keep with FF and for the flash pan use FFF or FFFF if you can find it. I would get the firearm checked out by a gunsmith if you can find one that knows about real old guns. All the load information I have is for modern muzzle loaders, not like that old girl you have. I would think around 35 grains of F powder would be a safe start with #7 shot, I use that load in my .50 caliber pistols and a round ball. It's around a .69 caliber so don't go shooting any round balls out of it, you might burst the barrel
Have fun and be safe

WD wrote on 05/11/14 at 08:25:53:


Thanks, that's some good info. That sounds like you have a real heirloom piece there, also. And yup - I live in Gig Harbor. So the PBers sound like the place to go. Now the bad news. It arrived OK, but was in a broken case, apparently had been in a storage locker or something for those 2 years while the other kids argued. Moisture got to it, so now I have a damaged stock and a rusty barrel. It has a well made caplock, which after a thorough cleaning and relube, looks and works good. I am researching methods of restoring the rest of it. Regarding shooting it, I have no experience with a B/P front stuffer shotgun. Rifles, cap and flint - lots. Even a finicky C&B wheel gun (sold that one!) My go-to field gun is a Charles Daly O/A .410, which I reload the hulls with American Pioneer Jim Shockey Gold 3F (BP substitute, as black powder is illegal here - classified as a low explosive). But stuffing a 3 inch hull on the work bench is a lot different than a running all that powder, shot and wad down a 30 inch barrel (outside, in the wind and rain, of course!). Also not so good, they didn't send the possibles bag, so no cleaning attachments. So before I get to shooting, I have some busy work to do. But Thanks to all for you responses.