Agree with what he said up there^^^^. So long as (a) you stick to black powder or a BP subsitute, like Pyrodex, and (b) NEVER fire without the bullet being fully seated against the powder charge, you will not hurt it.
ROUGH rule of thumb- 150-200% of the bore diameter in a RIFLE equals powder chage. In other words- 60-90 grains for a .45. Mostest is not always bestest.
PS- there are two kinds of muzzleloading shooters- those that HAVE forgotten to load powder before ball, and those that WILL forget.
What we have here is... failure- to communicate.