I saw specs for a 9.3 RCM, which could be trick if you want a lot of thump in a short action. Would have slightly more capacity than a 9.3 Barsness-Sisk, which is on a necked-up .350 Remington Magnum case. I believe the 9.3 Sisk is based on a necked-up 8mm Remington Magnum case. You can go to Charlie's website and get the details on anything he builds.
If I wanted to hurt myself that way, I would build a 9.3-.375 Ruger. There would be no particular point to it, but then having a particular point of utility would not generally be the point of wildcatting anyway
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Dennis