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View Full Version : Bismuth for non toxic boolits? yes no?



Survival Bill
01-08-2018, 12:29 AM
OK I was just thinking that since Bismuth is used as non toxic shot for shotguns will this be used for bullets at all or is it to hard and expensive compared to solid copper boolits..
And what about for us casters is Bismuth even an option if a lead ban happens does it melt at temps = or close to lead? would it work with current molds?

I'm just thinking out loud and sharing OK....

Mr_Sheesh
01-08-2018, 12:58 AM
Bismuth has a Brinell hardness of 70–94.2 Melting point of 544.7 K ​(271.5 °C, ​520.7 °F) so it melts at a lower temperature than Lead; You should be able to Sabot or Paper patch it, not sure it'd do well engraving the rifling. (Could try copper driving bands, too, tho precision would be an issue there!)

brewer12345
01-08-2018, 01:06 AM
Well, how about all-tin boolits?

Mr_Sheesh
01-08-2018, 01:56 AM
292–441 (cast)

https://en.wikipedia.org/wiki/Hardnesses_of_the_elements_(data_page) is a good resource :)

Bigslug
01-08-2018, 02:05 AM
Rotometals already offering: https://www.rotometals.com/lead-free-bullet-casting-alloy-88-bismuth-12-tin/

My pop the Retired Old Man Of Leisure has tinkered with it, though not lately. In shooting water jugs, we found that it wanted a higher percentage of tin to hold together on impact, though how it would do in meat is still up for discussion.

Our conclusion was, it's potentially an option to keep hunting with your vintage iron, but if you're hunting with common diameters (6mm, 7mm, .308, etc...), the Barnes coppers work well and are probably less grief. Another question is how to confirm to the fish & game cop in the field that the gray lump of metal in your magazine isn't what it looks like.

Short version - It's gonna take some time and effort. We've had almost a thousand years of figuring out how to shoot lead. Other projectiles, not so much.

243winxb
01-08-2018, 10:06 AM
Pure tin to expensive. I researched Bismuth a few years ago. This is what i found.


Properties of Fusible Alloys
The chief component of Fusible Alloys is Bismuth, a heavy, coarse crystalline metal that expands when it solidifies. Water and Antimony also expand on freezing, but Bismuth expands much more than the former, namely 3.3% of its volume. When Bismuth is alloyed with other metals, such as Lead, Tin, and Cadmium, this expansion is modified according to the relative percentages of Bismuth and other components present. As a general rule, Bismuth alloys of approximately 50 percent Bismuth exhibit little change of volume during solidification. Alloys containing more than this tend to expand during solidification and those containing less tend to shrink during solidification.
After solidification, alloys containing both Bismuth and Lead in optimum proportions grow in the solid state many hours afterwards. Bismuth alloys that do not contain Lead expand during solidification, with negligible shrinkage while cooling to room temperature.
Most molten metals when solidified in moulds shrink and pull away from moulds, failing to reproduce fine mould detail. Because Fusible Alloys expand and push into mould detail when they solidify, they are excellent for duplication and reproduction processes. This characteristic of expansion and/or non-shrinkage, combined with low melting temperature and ease of handling, are the major reasons for their extensive use. A number of eutectic* and non-eutectic alloys have been standardized.