how is it possible to overload sidelocks? barrel is 1/2 in thick! I reload for rifles and shotguns and steel much thinner. not sure about the differences in metalurgy and steel hardness etc but ya should be able to shoot a stick of dynamite in M/L - black powder vs smokeless (has much more pressure)! only limiting factor i can think of is nipple.
cant barrel take pressure of 200- 300 gr BP if ya wanted to?