Knight Mk 85----Need advice for bullet and powder

Been need some help on an older knight Mk85 50 cal I got from my dad and he’s never shot it. I’ve shot it a few times and converted it to use 209 primers. and just needing some help on a good bullet and powder. I saw a post where you talked about a patched bullet and I do reload and cast my own but have only been into that for a couple years now. Any help would be greatly appreciated.

RZingler what is twist rate on your knight? Sorry for the delay in replying this time of year bunch of us are out kicking trees to see if a deer or elk are under them (-; I myself only shoot cast conicals in my 50 cal pistols and rifles 1/28 twist at present shooting a cva optima with a Lee 460gr RN sized from .515 to 503 all lead, 95gr T73f, .54 OP wad then bullet set firm on powder. One thing to note try (all kinds) of 209 primers I randomly switched to some cheap CHEDITE brand to save my good primers for hunting and my group shrunk to +-2" at a 100yds I'm not saying that will always be the case but experiment with your loads also NO EXCUSES and BULL SHOP brand bullets shoot very good so look them up on line. Any questions fire away.