A guy that goes by Busta on another board shoots a 200gr bullet in a 50x40 sabot in his CVA Optima Pistol. Considering the fps limitations, a 40cal 200gr XTP sounds like a good fun load with the potential for smacking deer also. Busta shoots a 200gr SST over 80gr IIRC.

You could surely do the same thing with 50x45 sabots and some cheap 45ACP bullets too for recreation.