Any Guidance on Casting .25 Bullets? (Plus .458?)

Hi Gang

I’ve gotten into bullet making for my .458 Quakenbush and I’m tempted to get it a try for my .25 Condor.

The purpose is to get 51 grain-plus bullets given how 43 grain En Juns are the max commercially available.

Questions:

– Accuracy of cast .25? Important to me.
– what’s the best lead mix? I bought $40 pounds for $1 per from a Craig’s list guy so I don’t know what I have to start. I want soft but that’s not based on knowledge, I just want expansion and splatter, if even possible with condor velocity.
– which mold? I found the 51 grain version and a .258 / 65 with nose gas check.
– I understand the .258 needs sized. Is there a correct commercial available die size?
– what is correct size for the .458? I can’t find dies exactly .458. Is 457 ok? I have a .457 die.
– Is it worth casting the .25 to get more down range power? I would still get King heavy/En Jun for plinking.

Sorry for the many questions. Thanks for your help!