I've got a .510 Wells Mag. and I'd like to shoot some cast bullets with it. I cast 437 grain bullets for my 50-70 Govt., and I would like to try shooting them in the .510 at reduced power. Somewhere around 1500 fps. would be cool.

Unfortunately my 500 Jeffrey isn't finished yet, so I don't have any data. I would recomend starting with 15 gr unique, working up in 1 gr increments, til you get the velocity you are after, or till accuracy is decent. I use 15 gr unique and a 200 gr cast for 1500 in the 35 whelen, I know in the much larger case, you'll be at lower pressures. 2400 would also be a good powder to use, but you'll have to use heavier charges.

Well, finally able to help someone out.

I just so happen to have a load for cast bullets that the good folks at Accurate gave me.

XMR-5744 35 grains with a 575 grain cast, gas checked bullet. Gives me about 1050 feet per second.