My Optima shot very well with 245 and also 300 gr Hornady XTP with 110 gr loose 777.
If you want a 200 yard load, do some serious analysis with a ballistic software package. There are several that you can download off the Internet for a free 30 day trial. Put in the Ballistic Coefficient of the bullet of choice (obtainable at the bullet mfg web site) and also a close estimate of expected velocity (from either the powder mfg or CVA's website).
Be fore-warned that if you site your rifle for 200 yards it may be too high at 100 yards. Muzzleloaders may be a lot faster than they were with patched round balls, but they still have short & fat bullets with terrible BCs, being pushed at modest (at best) velocities. You may have to sight your gun to hit 4" low at 200 yards and still be 3 or 4" high at 100. Personally I have mine sighted for 1" high at 50 and 100 yards, 1.5" low at 125, and 6" low at 150. (That's with the 300 gr bullet and 110 g 777.) Then I hunt where my shots would most likely be 30-75 yards.