.36 balls are .375 so .357 bullets would be too small and you should only use soft lead in a muzzle loader, ok if you have the mold and cast them in lead.

Logically you would think conicals having better contact with the rifling should be better, but personally I think the weight is too much for the charge. They tend to tumble and keyhole the target on light loads, and if you stoke it hotter they strip on the rifling because they are soft lead so again tumble.