1911Tuner
Moderator Emeritus
Better yet, make up some 16:1 and test it against pure lead.
If I wanted to make lead harder, how?
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rcmodel
Member in memoriam
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At the price of tin, you are wasting your money trying to harden bullets with it.
Lyman # 49 lists the following:
Pure lead = BNH 5
Wheelweights = BNH 9
97% lead 3% Tin = BNH 9
94% Lead 6% Tin = BNH 11
91% lead 9% Tin = BNH 11.5.
92% lead 2% Tin 6% Antimony = BNH 15
84% Lead 4% Tin 12% Antimony = BNH 22
rc
zxcvbob
Member
Sell the batteries. Use the money to buy lead pipe or something. I got $9 and change for an old car battery from the metal recycler a few months ago, and it wasn't even all that big a battery. If you melt it yourself, there is very little usable lead -- mostly it's lead oxide and lead sulfate.
The lead that's in a modern battery is alloyed with calcium and/or stronium instead of antimony. When you mix calcium-lead (batteries) with antimony-lead (wheel weights), the calcium and antimony combine to make an intermetallic compound that you'll scoop out with the dross. If that gets wet, it gives off stibine gas, which is more toxic than cyanide.
The lead that's in a modern battery is alloyed with calcium and/or stronium instead of antimony. When you mix calcium-lead (batteries) with antimony-lead (wheel weights), the calcium and antimony combine to make an intermetallic compound that you'll scoop out with the dross. If that gets wet, it gives off stibine gas, which is more toxic than cyanide.
1911Tuner
Moderator Emeritus
The problem with using antimony to mix with pure lead is that a standard electric casting furnace won't get hot enough. The melting point of antimony at sea level is 1167.13 °F. Call it 1167 even. At that temperature, you're creating lead fumes. Not good.
Antimony pretty much has to be added already alloyed with lead in order to readily fall into solution. That means using one of the type metals or fairly expensive magnum shot if you need a high antimony content. Wheelweights have been cut back on the antimony and arsenic content, and more are showing up with calcium as a hardener/strengthener, and bullet quality suffers.
Tin, on the other hand, will alloy with lead easily, and with a lower melting point...lowers the necessary temperature for casting good bullets. The drawback is that it's expensive these days. Very.
The good news is that high antimony wheelweights can still be had if you can get in cahoots with a truck shop that services big trucks. Those still have the old 6% antimony alloy...with a little tin...probably about 1%, and some arsenic if you want to water-quench. Long considered to be perfect pistol bullet alloy, though a bit hard for my tastes and I get lead fouling with it in certain pistols
For what it's worth, I've never found any real advantage or need to go higher than about 11.5-12 bhn for pistol bullets, and have shot it at top-end magnum revolver velocities without problems.
Antimony pretty much has to be added already alloyed with lead in order to readily fall into solution. That means using one of the type metals or fairly expensive magnum shot if you need a high antimony content. Wheelweights have been cut back on the antimony and arsenic content, and more are showing up with calcium as a hardener/strengthener, and bullet quality suffers.
Tin, on the other hand, will alloy with lead easily, and with a lower melting point...lowers the necessary temperature for casting good bullets. The drawback is that it's expensive these days. Very.
The good news is that high antimony wheelweights can still be had if you can get in cahoots with a truck shop that services big trucks. Those still have the old 6% antimony alloy...with a little tin...probably about 1%, and some arsenic if you want to water-quench. Long considered to be perfect pistol bullet alloy, though a bit hard for my tastes and I get lead fouling with it in certain pistols
For what it's worth, I've never found any real advantage or need to go higher than about 11.5-12 bhn for pistol bullets, and have shot it at top-end magnum revolver velocities without problems.
243winxb
Member
Tin Increases Hardness
From Rotometals-http://www.rotometals.com/Bullet-Casting-Alloys-s/5.htm See bottom of page.
Basic Rules for Harding Lead-
For every 1% additional tin, Brinell hardness increases 0.3.
For every 1% additional antimony, Brinell hardness increases 0.9.
For a simple equation,
Brinell = 8.60 + ( 0.29 * Tin ) + ( 0.92 * Antimony )
From Rotometals-http://www.rotometals.com/Bullet-Casting-Alloys-s/5.htm See bottom of page.
Basic Rules for Harding Lead-
For every 1% additional tin, Brinell hardness increases 0.3.
For every 1% additional antimony, Brinell hardness increases 0.9.
For a simple equation,
Brinell = 8.60 + ( 0.29 * Tin ) + ( 0.92 * Antimony )
Last edited:
dragon813gt
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This is a very good overview of the Metallurgy behind cast bullets.
http://www.lasc.us/Fryxell_Book_Chapter_3_alloySelectionMetallurgy.htm
For those considering smelting down battery plates. If you have a death wish go for it. It's not worth the risk. There are plenty of other sources of lead to be had.
As far as buying specific alloys. Just go to Rotometals. They have competitive prices and are quick with the order processing. I just wish they weren't on the other side of the country. I find it amusing that they are based in California since they are the ones that push all the lead bans.
Brought to you by TapaTalk.
http://www.lasc.us/Fryxell_Book_Chapter_3_alloySelectionMetallurgy.htm
For those considering smelting down battery plates. If you have a death wish go for it. It's not worth the risk. There are plenty of other sources of lead to be had.
As far as buying specific alloys. Just go to Rotometals. They have competitive prices and are quick with the order processing. I just wish they weren't on the other side of the country. I find it amusing that they are based in California since they are the ones that push all the lead bans.
Brought to you by TapaTalk.
RustyFN
Member
Lino and Mono melt at 446 degrees F and cast at 572 degrees F. I use mono and lino in casting and never go over 750 degrees.
1911Tuner
Moderator Emeritus
Yea, because the antimony is already alloyed/in solution in type metals. Trying to alloy pure antimony with pure lead presents a problem because of antimony's high melting point.
If it doesn't melt, it doesn't mix.
zxcvbob
Member
That's not entirely true -- it could dissolve. (Gold will dissolve in lead. Aluminum will dissolve in mercury at room temperature) I don't know if pure antimony will dissolve in lead; I suspect it will but is painfully slow.
http://www.noogenesis.com/pineapple/blind_men_elephant.html
Recently I was offered bottles of mercury, I turned the offer down, there are those that would jump at the offer, mercury has an infinity to lead.
I was offered a 1 1/2 pound bar of Cerrolow 117, I turned it down, great for using when bending copper tubing, then there are hickeys, most useful when bending tubing.
Then there are reference books before the Internet, 60+ years before the Internet. Question?, Believe the reference material or believe the information available on the Internet.
I noticed the Los Angles shooters added a couple of concepts in the last few years, time is a factor and a chart for melting lead with tin. temperature melting point by percentage and the effect tin has on the hardness of lead.
http://www.worstpolluted.org/projects_reports/display/65
F. Guffey
Recently I was offered bottles of mercury, I turned the offer down, there are those that would jump at the offer, mercury has an infinity to lead.
I was offered a 1 1/2 pound bar of Cerrolow 117, I turned it down, great for using when bending copper tubing, then there are hickeys, most useful when bending tubing.
Then there are reference books before the Internet, 60+ years before the Internet. Question?, Believe the reference material or believe the information available on the Internet.
I noticed the Los Angles shooters added a couple of concepts in the last few years, time is a factor and a chart for melting lead with tin. temperature melting point by percentage and the effect tin has on the hardness of lead.
http://www.worstpolluted.org/projects_reports/display/65
F. Guffey
NO to batteries, but the posts are good. Sn for fillout, Sb and chilled shot for hardness, oven heat treated (450F and dumped in cold water). Sb will harden but it takes a couple weeks. > 2% Sn is a waste. > 5% Sb is brittle. Google Bumpo680's alloy calculator or try castboolits site.
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