Checking in late here Savagescout, but of course I think you own a great looking rifle.

Trash those sabots.

Bullshop 460 or 500 grain sized to .504 or .5045
Overpowder wad (1/8" nitro cardWAD-510-Afrom TOTW is my choice)
80 grains of T7 FFg or 85 grains of Pyrodex P.

You could use the #11s no problem if you had a cap hammer - sounds like you have the primer hammer on there. Tom Lodge or Doc can fix you up with a cap hammer pretty reasonable. Or..... I doubt you ever use 209 primers in that rifle so kill the tit.

I'm pretty much ignoring any previous mention of myself in this thread.