Arsenic in the alloy ??

[Johnch]

I was trying to work , while the customer talked to me today .
He was babbling on about how he used to casts bullets .

I zoned him out for the most part .
But I heard him talk about how he used a alloy with Arsenic to produce real hard bullets .
I didn't catch most of that line of ................ and didn't want to ask any questions to slow myself down more .

He also said if I wanted some , come back next week and he would give me some ingots of his alloy to use .

Now I have never heard of Arsenic in a alloy , But I don't know a lot about some parts of casting .
But hanging around here to learn .

Is he full of BS , or is Arsenic in the alloy usefull ?:confused: :confused:

If so how and why ?
Also if usefull how much should there be ?
Is the alloy dangerus to cast with ?
Or are normal precautions enough ?

Johnch

[felix]

Arsenic is a dandy hardener. If you smell garlic when melting it down, keep cutting the alloy in half with WW until you can no further smell the garlic. Make sure you do it outside, far away from the wind hitting your house (open window). ... felix

[chunkum]

As Felix stated, arsenic is a fine adjunct to hardening bullets cast from a plumbous alloy which also contains antimony and tin. Although the "sniff" test for determining if enough arsenic is present is new on me, it makes sense in a way if your sniffer works good. I'm not sure what percentage is necessary but the lore I've encountered concerning arsenic content for purposes of heat treating or water quenching hardening processes is that only a very small amount is needed. Most wheel weights are said to already contain enough, though some casters (including me) like to put a tsp or so of chilled shot (for their relatively high arsenic content) for five to ten pounds of alloy.
Best Regards,
Chunkum

[ANeat]

The way I understood it was they add arsenic to the lead not only for hardness but also to reduce the surface tension. That allows the shot to form into a sphere better when it is dropped.

Which is why you see it in lead shot more than anything.

Adam

[Bucks Owin]

The way I understood it was they add arsenic to the lead not only for hardness but also to reduce the surface tension. That allows the shot to form into a sphere better when it is dropped.

Which is why you see it in lead shot more than anything.

Adam

That's interesting. So, if I put a teaspoon of shot in the ol' Prod Pot it'll help the alloy fill out the mowld better? (Because of reduced surface tension...)

Dennis

[Johnch]

Thanks for the info .

I had to do more work for the old coot today .
So he gave me 4 whole 1 lb ingots :( :(

I guess it was free LOL

I will try a little shot in the aloy after I use up my big score

Johnch

[Firebird]

My understanding is that Arsenic is what allows heat-treating to work, but you only need less than 0.1%, which isn't much. Magnum shot has several times this much, and is a good source as is WW.

[Junior1942]

The way I understood it was they add arsenic to the lead not only for hardness but also to reduce the surface tension. That allows the shot to form into a sphere better when it is dropped.

Which is why you see it in lead shot more than anything.

AdamThat is correct. Except I don't think it makes the alloy any harder. In shot, the arsenic content is 1% to 3%. And you don't want to be sniffing the vapors!!

I have about 300 lbs of used, mangled lead shot. It's very soft, soft like pure lead, which it is exept for the arsenic. When it's in my melting pot, I make sure the wind is blowing the fumes away from me.

[Bass Ackward]

The finer grades of Magnum grade shot have the highest antimony and arsenic contents. But if you get over about 1% in your mix, then you get surface cracks in your bullets. It helps if you elect to use some tin to balance it out.

To give you an idea of what it will do, for those without a hardness tester, I get 12 BHN from straight WW. If I add a plastic cap full from a furniture or spray paint can lid, of magnum grade #9 shot to a 20lb pot, the bullets will air cool to 13 BHN. Add a little tin and I end up with 14BHN.

But I only add it to stuff that I want to HT well at lower temperatures. Like if I mix 50/50 WW and pure lead, it will HT to 16-18 BHN but the temperature spread is very narrow. Miss it by 10 degrees and you end up with 12 or 13. If I add the cap full of shot, I can HT at 425 degrees for 45 minutes and get at least 16 every time. So for me this is worth the added cost.

Just so you can decide.

[DLCTEX]

1 to 11/2% arsenic is all that is necessary, and all that can be utilized. Any more is excess.

[Finn45]

?? I've understood that other way around, meaning that arsenic (As) increases the surface tension making alloy to form spheres more easily during the fall from the tower. Also I've understood that arsenic makes hardening possible, but excessive amount actually makes casting more difficult due to increased surface tension, no good fill and voids etc. No? Pure lead has higher surface tension than lead-tin alloy and is more difficult to cast; how about hard lead shot alloy, is it easier to cast than pure lead?

[felix]

Arsenic increases the surface tension. Other elements do also, but they make the shot softer, and so are not used in lieu of the arsenic. Bismuth makes hard shot too. I do not know if arsenic is used in the bismuth shot. ... felix

[felix]

Arsenic also increases the slush period of a lead alloy which contains antimony and tin. Longer slush periods do generate wider heat threating temperatures like BA says. ... felix