I bought a CVA Wolf which is some what a "version" of the Optima just to see if Muzzeloading is for me. I've shot 250gr Power Belts, 250gr Saber Tooths, 300gr XTP and Knight Red Hots in 250gr. Also going to try some 300gr Red Hots as soon as it cools off. So far I've gotten good groups with about all of them but I've chossen the Knight Red Hots with Crushed Rib Sabotsto hunt with. They are also sold as the Barnes MZ Expanders. I've done some experimenting with the pellet and loose powder, My CVA has been shooting better with100gr Pyrodex pellets. I also use 209 Remington Kleen Bore primers. You'll just have to get different bullets and try them out to see which combination your Optima will shoot. And don't be afraid to ask questions here. I've learned a lot from these guys by reading their posts and posting questions. Good luck.