Lead Composition

[Guy La Pourque]

Hi Guys,

I am in the process of nailing down my lead supplies to reload for a Uberti 45-75 replica. A supplier is telling me they have 12.5 lb. bars as follows:

Tin (Sn) 0%

Antimony ISb) 6.5-7.5%

Arsenic (As) 0.30-0.60%

Lead (Pb) balance

Is that lead hard enough to cast with? Or do I need to throw in something else? Your advice, as always, is sincerely appreciated.

Cheers,

Jim

[grouch]

Jim: I'd say PLENTY hard enough. It probably needs 2-3% tin to cast well. For what it's worth, my 45-70 much prefers 18:1 lead and tin, as do several of my other rifles. I can only speculate that it would likely do better for you too at any velocity you're apt to want to shoot in your 45-75.
Grouch

[dtknowles]

That lead would be hard enough for most applications but might cast a higher percentage of good bullets with a little Tin, like 1 or 2 percent. With that Arsenic, if you need harder bullets, you could water drop harden them.

Tim

[Larry Gibson]

I would add and equal weight of pure lead which would cut the antimony level in half. I would then add 2% tin (by weight) to that for an excellent alloy for your 45-70. I would use that for smokeless loads.

Larry Gibson

[KYCaster]

Sounds like magnum shot alloy....currently selling for ~$1.80/lb.

Way more Sb than desirable....way more As than necessary.

I think a binary Sn/Pb alloy would be more suitable....25 lbs. of plumbers lead and 1 lb. of 95/5 solder (or 2 lbs. of 50/50 ) would be a good start.

Jerry

[Guy La Pourque]

Well thanks, boys.

Where does a fella get tin? I can cut this stuff with pure lead, I suppose...and add a smidge of tin...

[dbosman]

A quarter pound of lead free 95% tin, 5% antimony solder would work, if you do as Larry Gibson suggested and add 12.5 pounds of relatively pure lead to that ingot.
That 25.25 lbs of alloy will get you what? about 500 boolits?

[MtGun44]

Probably too hard. I suggest you look for a 1:20 or so tin:lead alloy rather
than an antimony alloy. You do NOT need harder for that cartridge.

"it this hard enough to cast with" is entirely a false premise. That cartridge was
originally loaded with VERY soft alloys, probably 1:20 or 1:30, tin:lead. You
are more likely to find success the same place that Winchester originally
found it. I am assuming it is a 1876 Win.

[Guy La Pourque]

It is, Mountain Gun! I have stocks of supposedly pure lead and the boys tell me if I alloy it with some tin solder I should be good to go. I just need to find a supply after that runs out...

[Bret4207]

Probably too hard. I suggest you look for a 1:20 or so tin:lead alloy rather
than an antimony alloy. You do NOT need harder for that cartridge.

"it this hard enough to cast with" is entirely a false premise. That cartridge was
originally loaded with VERY soft alloys, probably 1:20 or 1:30, tin:lead. You
are more likely to find success the same place that Winchester originally
found it. I am assuming it is a 1876 Win.


(Sigh) That HARDCAST krap is even getting over into BPCR now. Sad.

[MtGun44]

I'd start with 1:30 if I was short on tin. Then go to the commercial houses for your metal if you
can't find scrap sources.

There are suppliers, some are sponsors of this site, that (I believe) provide 1:20, 1:30 and maybe
even 1:40 alloys for those that are shooting BP guns.

Bill

[GlocksareGood]

So how much are the bars? Can't leave that out! :)