Yes - by all means, pictures are requisite.
; With .030"deep rifling, it would have a 1.044"groove depth. However as it is a muzzleloader, it would be more correctly called a 5 bore.
; The barrel walls at the breech at .138" are probably OK for light charges, say, up to 200gr. without trouble other than recoil.
; Measure the twist rate and you'll probably find a rapid twist. This does not mean it was meant for slug, as it would have been made MUCH heavier if it was. It just means it will shoot a light load fairly accurately.
; I'd have a round ball mould made that cast around .975"". That would allow using a descent denim patch of about .018" to .022" thick. Afterall, you want to hit what you aim at and the patch must seal to give good, accurate, clean shooting.