Originally Posted by
dtknowles
I is absolutely easy to put enough fast powder in that small case to create more pressure than is safe so the small case can make more pressure than the long case if that is how the ammo is loaded. The 32 S&W long wadcutter factory ammo is almost always loaded to lower pressures than all the other 32 S&W ammo because that is what the shooters who use it most want, not really the lower pressure but the lower recoil and lower blast because they are shooting at paper targets with precision not how good it might be at killing something.
Regarding the stories about the non-linearity of CUP vs. Psi being caused as you described, it is just a theory. There is very little data on the performance of materials when subjected to impulse loading (short duration high loads). It is clear that such a phenomenon as was suggested is real but it is not documented (or at least I have not been able to find such documentation) that this it actually the case. That you did not really understand it is not a surprise, it is not well understood. There are other theories about that as well but just it is good to know that the pressure might be higher than CUP suggests and using PSI data is probably better.
Tim