I'd need to double check notes, but the XTP 300gr jacketed hollow point and a case full of rifle powder.
Ridiculous energy, ridiculous recoil - out of the 45/410 contender handgun.

I also ran loads that were mild and manageable.
There is a lot of room for a wide range of loads.
My advice is to maintain a high load density and use magnum primers for the smokeless rifle powder.
I don't recall using black in the 9.3 brass, but I'd definitely give it a go. Lots of case.capacity. Large pistol primers would be good for the black powder loads, if you will be using real black powder.

The long brass just makes it easy to reach the chamber throat, and the 9.3mm brass is very tough.