Got interrupted, but to continue I didn't realize how little you know about pressure-testing. No company I know of has used copper-crusher testing for a number of years. Instead they use either strain-gauge or piezo, partly because they're generally more accurate and provide more information, and partly because they're a lot quicker.
Consequently, the data that still appears in CUP is old data, and not only probably isn't as accurate, but doesn't include the latest powders. It usually appears for cartridges that have been popular for a long time, because the company doesn't want to take the time away from electronically testing newer cartridges and powders. This is because handloaders are clamoring for the new data, so the electronic data for older powders gets squeezed in here and there.
Also, NONE of the Hodgdon PSI .223 data for 40-grain bullets is even over 50,000, when the SAAMI maximum for the .223 is 55,000 PSI. It doesn't even approach the potential of the cartridge. I don't know why Hodgdon does this with the .223, though I have my suspicions. Might have to ask the head ballistician next time I talk to him.
ALL of the Hodgdon .204 40-grain data is over 50,000 PSI and a lot over 55,000, because the SAAMI limit 57,500 PSI. So you were indeed comparing apples to oranges.
In contrast, all the other data from seven other sources that I added in is electronic, not copper-crusher, for BOTH cartridges. As a result comparing it is far more valid than comparing the data from ONE company that doesn't use the same pressure standards or equipment for both rounds.
And you also figured the recoil energy of both rounds from your limited, skewed data.
You continue to astound me. What company do you work for?
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