I bought some 520 gr. boolits from a Lyman mould 457125. The Sharps seem to like heavy boolits so I thought I would give these a try. There is no loading information I can find on these beasts. I have loaded them with both 5744 and 1 1/2 F powder. Has anyone had any experience with these? They are a .458 size lubed with SPG. I would like something around 1100FPS but I don't have a chronograph to check their speed. I was hoping to find someone that may have used these before and was curious what you have found to be a good place to start with these. The 500 gr. boolit loads seem to be O.K. but with these big boys I can't seem to get what I would like out of these guys. I am shooting a 30" Shiloh Sharps and a 32" Pedersoli Sharps. Any info about speed would be greatly appreciated.