30 years ago I went to a duck and goose calling seminar in Middle River. It was in a high school gym.
They showed a movie of an OLD guy that would shoot birds with a Side By Side. After he fired, he would take a hammer and punch and remove the primer, Pound in a new one and then pour in SOME black, no measure just pour in a little. Then he would stuff some dry grass in and pour in SOME shot. Stuff some more dry grass in to compact the shot and beat it into the side by side with the palm of his hand. He was killing geese with these shells, in the movie.
Sometimes we make things way too complicated
Man you have no idea how too complicated guys can make thing trying to be so overly technical in explaining themselves. Loading a Muzzleloader is not rocket science. Shotshells and other reloaded ammo can be as simple as you need it to be to do the job.