jmf,
I would not hold my breath on a response, I imagine that those who have tried will not be able to respond.
However I read somethig from a top notch company. Not sure but I think it was T/C or Hogdon. They stated this myth was based on the fact that some fealt black powder could only develop a
max psi. The company had been conducting R&D testing on a new product. They started to increase load sizes to see if this myth was true. They deturmined that as far as in ml application no max psi limit was obtained with black powder. In fact, at one point muzzle fps stoped increasing and started to decrease but psi kept climbing.
I think in my case I would need exceed the manufactures recomended load by 24 times just to feal the barrel.
No thanks!!! I will stay between 95 and 115.