What pressures do Pyrodex pellets operate at?

[Cossack]

Black powder CARTRIDGES operate at around 20,000 compared to 55 to 60,000 fps (and higher) for metalic cartridges. I'm (guessing) that Pyrodex or 3T7 operate at substantially less than that in a muzzleloader. But what happens when you seat a bullet over them in a case, add crimp and more direct spark is anyone's guess. I'd campare the Pyrodex load to a safe black powder load if you can find that data. E.g. 50 grs of BP would equal one 50 gr Pyro Pellet (which are actually shy of 50 grs) That said, I'd get a long string for the first firing.....just in case.

PS My muzzlelaoder pistol says "do not use pellets" but I have no idea why not.