[Unclenick]

Jim W,

The SAAMI maximum data I cited was for Piezo transducers, and not crushers, but I didn't bother to mention that because those different systems tend to be close at lower pressures. That happens because all pressure measuring systems converge at zero. U.S. Piezo and CIP Piezo and US copper crushers and CIP copper crushers all read differently at high power rifle pressures, but tend to be pretty close below 30,000 PSI. I assumed that would be true for the British measuring system too, but confess that I don't know at what pressures it's readings diverge significantly from the other systems? It might make for some interesting historical research? I have a pretty good chart for absolute pressure v. copper crusher in the .30-06 done at the U. of Michigan in the mid 60's, but have yet to find equivalent quality information for other rounds or other measuring systems.

I also found a disagreeing reference on the SAAMI pressure for the .38S&W. One has it at 17,000 CUP and 17,000 PSI, both separately listed, like the .38 Special, while another has it at just 12,000 CUP, that number listed alone. So it looks like I need to go to the horse's mouth on that one to see which is correct and whether it has changed over the years? I can't imagine they would raise it on a round mainly fired in older guns.