Lead free pewter is no harder to cast than lead. Does it melt at a different temperature, I’m sure it does, experiment with it. If people on YouTube can cast fancy googaas in a silicone mold with pewter melted over a burner on the stove, I’m sure I can make a bullet or two with my lead pot, and a mold.
And by the way the CDFW has testers that can detect lead residue from a bullet hole.
Hungry Horse
I have some britannia metal (one of the common lead free pewters) that I recently used to repair an old jewelry box. Britannia is 92% tin, 6% antimony, and 2% copper, and melts at just under 500f. I also have some Callahan bullet molds that have never been tested. Figured I'd give it a shot.
Was quite difficult to get it to pour into the mold, kept balling up and running over the side. Even after heating up the mold a good bit. Every time I've cast it into silicone, there was a much bigger hole. Maybe lead has a lower viscosity when melted, I've never actually tried to cast lead before.
I'm not that experience at casting any metals either. This recent jewelry box repair was my first foray into that world.
Had to get it a bit hotter than I liked for it to flow into the mold, and even that took a couple tries. Ended up just heating the mold with the propane torch till the metal I had inside remelted. The nice thing about it, is that it takes almost no time to melt with a propane torch.
You can tell from the purple and yellow oxidization that it got hotter than optimal. Still perfectly serviceable. In the midst of remelting things I don't think I kept the mold closed all the way. No big deal, the flashing came off with a finger.
Here's the weight of it compared to some identically sized lead balls from Kibler.
Lead seems to weigh almost exactly a third more. 33.46%
Ran some numbers to compare it to the brass balls. Pure lead seems to be around 11.348 g/cm3, and 260 Brass is 8.53 g/cm3. Lead weight is only 25% heavier than brass.
With a 58 caliber gun, I really don't know if those weight differences matter. It's possible that lead free pewter would expand better than brass. Could make up for lost weight.
Of course, you could also just work up a double ball load if you're worried about it.
I've shot a bunch of .54 double ball loads, .58 can't be too much worse.