Hello Pastor,
Right out of Lyman's Cast Bullet Handbook, 3rd ed.--#257420, 68gr, #2 alloy (I used 95% wheel weight and 5% 50-50 solder) Three loads listed--starting at 5gr unique (max 6gr); starting at 9gr 2400 (max 11gr); starting at 10gr IMR 4227 (max 12gr). I like 10.8gr of IMR 4227. There is also three loads listed for an 88gr cast bullet. I find the larger bullets take up too much case capacity.
The only factory bullets I use are the Hornady 60gr fp (#2510)--both in the Marlin 62 and the contender pistol.
I've been haunting quite a few forums now and this is the first time I've seen any mention of this cal. It surely is fun to shoot! Have you found any new brass anywhere? I gave up and bought an RCBS forming die set and make them from new .357mag brass. BigShooter