Not sure if this has been asked before, but what are your thoughts on the pressures generated in a muzzleloader like in comparison to the same load in a breech loader?
I would assume the same, but does it make any difference with the lack of a chamber, forcing cone, case head etc?

Also I seem to recall reading somewhere about an experiment where the chambers of a breech loader actually had slots cut in them from the breech to the end of the chamber. These were then fired without issue if memory serves me correctly. It may have been Burrard or Greener but I cannot find it. Can someone point me in the right direction?
Cheers,
GDU.