@runfiverun is the one who makes his own jackets
. That post was taking a stab at him.
He is actually well connected to a group of fellows that are experimenting with that stuff right now.
He used to run a custom bullet manufacturing company, and rubs shoulders with the likes of Glen Fryxell, and the ben that invented BLL.
Runfive run would be a much better source for your questions then I.
Now you can cast Zumac or Zinc bullets but they come out light and you have to use a iron or ceramic pot and a dipper set up to pour them. The temp is a bit higher then lead, and the zinc can eat right thru a Lee pot, and wear out a mould.. A large amount of work for a bullet that just seams to fall on its face after 10 yards. Elvis Ammo has posted a lot of videos about zink bullets.
Pluss Roto Metals has a new lead free alloy that you can get at a respectable price. It is in the experimental stages, but avalible. Some of fivers friends are experimenting with it right now for Roto.