Arsenic vs Antimony For Hardness?

[American]

According to LASC the 1/4% arsenic in WW alloy is very important to the heat hardening process:

"…and arsenic is even better for heat treating than is antimony…"

Does water-quenching somehow utilize the same mechanism for hardening as does oven hardening?

How important is the arsenic to hardening by water-quenching from the mold?

For example, if WW alloy is composed of 1/2% tin, 4% antimony, 95.25% lead and 1/4% arsenic (as per LASC) and these will drop-quench to almost the hardness of oven treated bullets, how much of that is due to the arsenic vs the antimony content of the alloy?

Further, if an alloy is made up to be like the WW alloy, but without the arsenic, how will these bullets harden when water quenched compared the the 'real' WW alloy with arsenic?

Is there a way to add arsenic to alloy besides using hard shot, which isn't really economically practical?

Finally, would adding more antimony help compensate for the lack of arsenic in the above alloy for the purposes of water-quenching for hardness?

[Pepe Ray]

The Lyman Cast Bullet Handbook(Manual) gives as much as info on this as I've ever read anywhere.
Lets not get too much discumbobalated by minutia.
1. by itself, antimony is a hardener. (.)
2. Heat treating is "the rapid reduction of temperature".(.)
3. Oven technique is more uniform in your ability to control the HIGH temp , and the TIME it takes to UNIFORMLY immerse the boolets into the coolant. (I've often considered that a blast from a CO2 fire extinguisher would be as good.)
4. Arsenic in VERY small amounts is a catalyst that ENHANCES the process.
5. The reason that the AS is minimal is that in larger quantities a characteristic of AS is that (like Zinc) i reducers the surface tension of the alloy. This is the reason you find the most convenient sources of AS being in SHOT. It is paramount in making the shot ROUND. Yes, magnum shot has more of it but regular shot is good enough to enhance the hardening of CB's. Sacrifice a few shot shells.
As long as a minor % is present it would be an exercise in academia to determine how much more or less to assist hardening was needed.
I'm not saying that no one but a laboratory staff could do it but, buddy, it would be a lot more work for very little gain than I'd want to do.
The book gives you temperature values and time parameters for oven treating and some day I may find it necessary to change from water dropping, but I don't see it in my near future.
I'm always scouring the posts on the sub, looking for the one where some poor soul has put too much AS in his melt and cant get good fill out and can't understand it because he watches carefully for the Zinc devil.
That's my story and ISTI. :) Pepe Ray

[blysmelter]

. (I've often considered that a blast from a CO2 fire extinguisher would be as good.)


CO2 in gas-phase doesnt really cool down anything effectivly as there is no liquide to evaporate and take away heat.

[American]

....
Lets not get too much discumbobalated by minutia. ...Arsenic in VERY small amounts is a catalyst that ENHANCES the process....Sacrifice a few shot shells.
...

So, add some Sn & Sb to Pb to a common alloy, cast and water-quench, and that would work pretty good. But if I add WW until they are maybe 1/3 of the alloy and that should provide significant traces of AS, and even though it won't be the 1/4% the WW industry clearly opines is the 'ideal' amount, some benefit will be gained in the form of harder rifle boolits. That would even be better?

Stress the details less, cast more, shoot more. :Fire: Sound's like a plan - I'm just trying to learn to do the best I can with what I have on hand, and buy as little as possible of expensive base metals. Thanks.

[leftiye]

Am, I think you're doing fine. The term learning curve applies here. The "minutia" we all pay vast attention to. You should always strive to know more (how else can you become an expert - ex= has been, spurt= pressurized drip) but you gotta play as you go (pun?). Seriously, it takes time to know it all, and it will make your product better, but we must function as per where we are on the learning curve. The trick is to enjoy!

[wiljen]

Many lead and antimony ores are contaminated with arsenic to begin with so it is an easy thing to get. When I did the group buy for +Metal, I discussed this at some length with the foundry. I asked if the alloy contained arsenic and in what percentage, He was worried about it until I told him it was a good thing that I was hoping for 1%. He laughed and said that Pure lead without trace arsenic is much more expensive than the stuff with trace Arsenic. Same for Antimony, most comes contaminated with .25-1% Arsenic.

Copper and I believe cadmium will catalyze the same reaction but cost more. Kind of like using tellurium instead of Antimony. Tellurium until recently was a by-product of other mining, now with all the flash memory cards using it, it has gone nuts price wise. I suspect at some point the people making WW said, whats the cheapest combination that serves our purpose. Antimony was far more common than Tellurium, and Arsenic being present as a contaminant prevented the need for copper or other expensive additions.

[longbow]

I have a handbook published back in the 1950's by the company I work for. Unfortunately I have been told I can't reproduce it but can cite information from it. I am still trying to get permission to reproduce it and I think I will but until then...

It is called "Application of Lead and Lead Alloys in the Chemical and Metallurgical Industries" published by The Consolidated Mining and Smelting Company of Canada, 1955.

Information from a couple of tables in it give the following information:

As cast air cooled lead/antimony alloys will range in hardness from 7 BHN @ 1% anitmony to 15.3 BHN @ 14% antimony.

A lead/antimony alloy with 4% antimony will be 8.1 BHN for cold rolled and 24 BHN if heat treated at 450 degrees F then water quenched.

The highest hardness listed is 26.3 BHN for 8% antimony heat treated at 450 degrees F, water quenched and aged 1 day.

My understanding is that wheelweights normally contain approximately 4% to 5% antimony and the table shows a BHN of 24 for this alloy when heat treated. I have read many claims of 30+ BHN for heat treated alloys so they must have other alloying elements in them to achieve that.

There is no mention in this handbook of arsenic for hardening lead though.

I often oven heat treat but don't have a lead hardness tester yet so don't know for sure what I am getting except much harder than ACWW.

Longbow

[454PB]

I've done considerable experimenting with heat treating, and tested the result with a Lee hardness tester.

One experiment that may be of interest was to mix pure lead 66% and linotype 33%, then water quench. No arsenic was "known" to be in this alloy.....but that doesn't mean it wasn't. Theoretically, this 66/33 mixture should have contained 1.3% tin, 4% antimony, and the balance lead. The sample boolits were tested daily, then weekly. They reached peak hardness of around 26 BHN at two weeks, then began to resoften to around 20 BHN.

Apparently arsenic is a catalyst for precipitation hardening, but not required.

[waksupi]

When lead is refined, it is impossible for them to remove all the native arsenic content in it, so all lead has a trace.

[Ghugly]

I just tried water dropping for the first time. I tend to go into sort of a frenzy when casting and found that I was damaging quite a few boolets by dropping them on top of other boolets. Dropping them into a 5 gallon bucket of water pretty much eliminated the problem. They look great and shoot just as well (.44 specials at around 800fps). I was kind of stunned when I noticed how hard the damned things are. I can't scratch them with my thumbnail. Out of curiosity, I dug a few out of the dirt bank to see what they looked like. I think they could be dusted off and reloaded! My alloy is 40lbs of WW to 10lbs of radiator solder. I'm not asking much of them, so the hardness really wasn't the point. I was just really surprised to see what a difference water dropping makes. If they don't deform when blasting them directly into dirt, I think expansion in hunting or defense is pretty much out the window.

[blackthorn]

454PB----Is it possible that rather than being a hardening agent per-sea the arsenic slows, stops or limits the tendency of the bullets to re-soften over time?

[454PB]

I don't know, blackthorn. Accepted theory seems to be that it is simply a catalyst. I have some heat treated boolits I made 25 years ago, and they are still hard. Since I didn't own a hardness tester back then, I don't know where they started, but from what I've seen since getting a tester, they resoften to around 20 to 22 BHN and stay there.

[38 Super Auto]

I think they could be dusted off and reloaded!

Ghugly, I have seen the same thing. Some of my bullets that I've recovered still had a fair amount of lube as well as being in nearly new condition.

I water drop primarily for the reason you mentioned - to reduce the potential damage. I do like water dropped bullets with high pressure/velocity loads.