50 KSI is a lot! I wouldn't pull the trigger without best earmuffs money could buy. That is the reason why I prefer 45 Colt over 44 Magnum; same bullet weight, same velocity, same punch, but 45 Colt will do it with less pressure.Might run afoul of the .500Special, don't recall its length. I would go for it but it would be a good bit more than that pressure wise. The JRH is 50,000psi and is already factory offered in the BFR.
BTW:
.500 S&W Special
Case length 1.274 in (32.4 mm)
Overall length 1.733 in (44.0 mm)
.500 S&W Special - Wikipedia
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