mmmmm no..If you want to fire them.., consider maybe retiring., If you lose a finger or Maim a hand ., it could very well damage your ability to provide for your family.
I have to go with Capn Glen (The Royaliste).
Do Not Cheap Out On Firearms.
Get one that works ., a real one and just go from there.
A Prop is cool for a festival..., but not intended to be used as a gunpowder combustion chamber.
Winchester has designers and engineers that lay this stuff out on paper..,Colt does.,Smith and Wesson do., Tower was tried and tested for a few Centuries....,
Probably better to experiment with a real weapon than creating your first one from a forum?
Choose wisely