I recently chrono'd my 50 cal. CVA Optima. Here's what I got:
.452 diameter 300 gr. Hornady XTP bullet
Harvester sabot
100 grains pyrodex powder
RWS 1081 musket caps
4 shots averaged approximately 1450 ft/second
I've been using 100 grains just out of convenience. I hunt with two 50 grain pyrodex pellets. I plan to chrono this gun again soon and see if I can work up higher velocities and better accuracy shooting off the bench. I have had no problem with stopping power from this bullet, but I'd like to extend my range if I can.