RotoMetals Lead-Free Mold Size

[Nuthatch]

I don't want to turn this into a political thread. Political winds blow lead free out here -- it is what it is.

I'm interested in casting some round ball for my Traditions .50 Woodsman. No experience casting yet so total newbie here. I've heard that bismuth expands a little on cooling. Combined with the harder material, I'm wondering if the same size mold can be used for lead and lead-free options or if I need to get different size molds for each casting job. If anybody has experience casting & shooting the RotoMetals alloy, I'd appreciate some input.

 

[Zonie]

Yes, Bismuth expands a bit after it has been cast.
It is not a great amount so if your shooting patched roundballs I think the small amount of expansion won't even be noticed.

Bismuth is harder than lead so don't expect it to compress as easily as lead when you are starting it and its patch into the muzzle. It also is not as ductile as lead so it won't expand as much when it hits an animal.

That said, a .50 caliber ball starts out as large as some modern projectiles expand to.

If your using it for hunting, make be sure to check out its accuracy by shooting some of them at a shooting range at a target. Adjust your patch/ lube and powder load to get the best accuracy and then take only well aimed, sure shots on the game.

 

[Boomerang]

Is Bismuth the same color as lead?

 

[Historian]

You need to alloy the bismuth with at least 5% tin. That will make it a little softer and will keep it from fracturing. You will find it does penetrate deeper than the softer lead. I make my own bismuth shot and roundballs and the 95% bis/5% tin alloy works great.

 

[Loyalist Dave]

RotoMetals sells several different bismuth/tin alloys. https://www.rotometals.com/lead-free-bullet-casting-alloy-88-bismuth-12-tin/ bullet casting alloy will be closer to a lead bullet being 88% Bismuth and 12% tin,but may be difficult to cut the sprue compared to other alloys. More bismuth = harder and more brittle. Roto202 is more tin at 62.5% Bismuth to 37.5% tin https://www.rotometals.com/roto202f...-tin-ingot-lead-free-alternative-to-roto203f/ so is becoming less brittle, while losing a bit of weight. This might be what you want. Fishing sinker alloy https://www.rotometals.com/lead-free-fishing-tackle-weight-bismuth-tin-alloy-281/ is 58%/42% Bismuth/Tin, which will be even lighter, and so your point of impact at distances beyond 50 yards may be higher, and you may have to resight your rifle. The advantage may be if you are hand casting with an aluminum mold like one gets from LEE, or a bag mold, you may find this alloy the easiest from which to trim a sprue. Technically, you could go with all tin or in a pinch, tin with silver by using solid core silver solder, but the bullets would be a lot lighter, and while they'd have a much higher muzzle velocity, might not have the mass you need to harvest the deer as you would wish.

All of them should cool with a larger diameter than pure lead. So you're going to need some range time for sighting as well as patch and round ball combinations.

LD

 

[BJHabermehl]

RotoMetals sells several different bismuth/tin alloys. https://www.rotometals.com/lead-free-bullet-casting-alloy-88-bismuth-12-tin/ bullet casting alloy will be closer to a lead bullet being 88% Bismuth and 12% tin,but may be difficult to cut the sprue compared to other alloys. More bismuth = harder and more brittle. Roto202 is more tin at 62.5% Bismuth to 37.5% tin https://www.rotometals.com/roto202f...-tin-ingot-lead-free-alternative-to-roto203f/ so is becoming less brittle, while losing a bit of weight. This might be what you want. Fishing sinker alloy https://www.rotometals.com/lead-free-fishing-tackle-weight-bismuth-tin-alloy-281/ is 58%/42% Bismuth/Tin, which will be even lighter, and so your point of impact at distances beyond 50 yards may be higher, and you may have to resight your rifle. The advantage may be if you are hand casting with an aluminum mold like one gets from LEE, or a bag mold, you may find this alloy the easiest from which to trim a sprue. Technically, you could go with all tin or in a pinch, tin with silver by using solid core silver solder, but the bullets would be a lot lighter, and while they'd have a much higher muzzle velocity, might not have the mass you need to harvest the deer as you would wish.

All of them should cool with a larger diameter than pure lead. So you're going to need some range time for sighting as well as patch and round ball combinations.

LD

If it were me I’d be using a tanner mold for non lead alloy casting. The molds are available in any diameter needed. Spruce cutting with modified wire cutters eliminate wear and tear on aluminum molds. Just my two cents.