Not familair with YOUR gun- I shoot CVAs and Thompson/Center, traditional STYLE muzzleloaders that are percussion cap weapons. First, MOST reloading manuals will have a short section on muzzleloaders. Second, never use anything but black powder OR black powder subsitute, such as Pyrodex, Triple 7, etc. Third- never load a "just fired" rifle- the spark waiting down there will put you in the ranks of the "No Eyebrows" club. Same applies to loading a capped rifle. 4th- There are two types of BP shooters- those that have loaded a ball with no powder, and those that WILL do so at a future date. Learn how to remove the bullet when ya screw up. Sequence is powder-ball-cap. Last- NEVER- I mean NEVER- fire a rifle that the bullet is not fully seated on the powder charge. If crud from earlier shots has caused you bullet to get stuck partway down the bore, trying to shoot it out may kill you. While this may be an improvement of the human gene pool (removing dumb people from breeding population) it is rough on innocent bystanders at the range.
As far as charge/ bullet- the traditional load is 1 to 2 times the caliber, in grains of powder. So a 50 caliber would use 50-100 grains of powder. Somewhere between those 2 numbers is the charge that will give you the best accuracy. However, that is for a patched ball- if you are shooting saboted bullets, most come with their own recommendations on powder charges. Damaging a rifle from overloading with black powder is not really possible- all that cannot burn gets blown downrange (and wasted) For caps- if percussion, usually standard #11 caps. If yours is a modern muzzlestuffer that uses 209 shotgun primers, there IS a 209 primer made JUST for muzzleloaders. Check your local gun shop.
Get a reloaders manual, contact the company (bet if you search, you'll find a website) take your time, and enjoy it.