Being a .58 (.577) caliber rifled musket it is made to shoot the hollow base Minie' bullets.
The original powder load for the typical rifled musket was around 60 grains of FFg powder. The short barreled "carbine" would probably be happy with a 55 grain powder load.
If you decide to shoot the Minie' bullets, try to find some that are just about .002 to .003 smaller than your guns bore.
If they are smaller than that, they usually aren't very accurate and if they are much larger you'll have a real problem trying to ram them down the bore.
There's a reason (beside historical) the powder load was only about 60-65 grains.
If it is much larger the higher pressure of the gas will "blow" the thin Minie' bullets skirt open as it leaves the barrel. If this happens, no telling where the bullet will head but it is seldom at the point of aim.
A lot of the owners of the .58 rifled muskets shoot .570 diameter pure lead roundballs with a patch.
These can be very accurate but because of the shallow rifling groove depth in these guns, they need to be tightly patched.
A .570 ball with a .015 thick patch is a good starting place.
Because the roundball doesn't have a thin skirt to damage, a lot of shooters up their powder loads into the 80-90 grain range.
Shot over a 90 grain powder load a .570 ball can be big medicine for about any critter in North America (except for Grizzly).
For you folks that don't know what rdillion has bought, follow this link
http://www.davide-pedersoli.com/sc...brother-cook-e-brother-artillery-carbine.html