In one of the older speer manuals, as I recall, there is data for the 7mm intl rimmed in the handgun section. It was one of the early wildcats for handgun silouette.
The problem I had was two fold. Contender frames stretch on firing, and thus you have to set back the shoulder when sizing to properly fit the chamber, and the 30/30 brass is thin.
With a Ruger #1 or #3, you don't have to worry about the action stretching on firing, and it sounds like there are other options for brass.
