You need one of the reloading manuals that lists cast bullet loads - Lyman's is a very common one. It also has casting instructions. If you can find one, get Lyman's old cast bullet manual (late 1950's or early '60s). Also join the Cast Bullet Association.
With respect to your other question, if you reload the traditional cast bullet loads( the low velocity ones with fast powder) you can reload most rifles for about half the cost of jacketted reloads or a quarter the cost of factory ammunition. These can be made to shoot very nearly as well as jacketted ammunition with far less noise and recoil. Your rifle barrel will last until you and your grandchildren are sick and tired of it, and you can use one rifle for a lot of things.
If you are dealing with a 30 - 30, there is little benefit to jacketted bullets, you can very close to equal factory velocities with cast. If you are dealing with 45 - 70, 38 - 55 kind of cartidges, you can do anything they can do with cast. I suspect that you could do good things with a 458 and cast, although I haven't tried it and don't plan to.
The quality of bullets you cast is limitted only by the care and attention you put into it. My normal run of .30 cal bullets is held to +/_ 0.2 gr. with the vast majority +/_ 0.1gr. At that quality I easily cast more than 100 bullets an hour.
I encourage you to get Veral Smith's book, it gives a much needed more modern view of what can be done with cast bullets at higher velocities, and a very good dissertation on bullet design.
And yes, it is enjoyable like handloading jacketted loads, but more challenging and you are rewarded by achieving a great deal more of the potential of your rifle.
Hope this helps, and you get a lot of enjoyment out of your foray into bullet casting.
Ron
