Heat treating question

[nhyrum]

OK, so for various reasons, I'm looking for an ultra hard cast boolit for my 454. Aiming to get around bhn of 30.

Currently, while casting, I drop into ice water, size, then bake for 45 minutes at 455, 10 degrees below slump temp, then drop into ice water, again, right out of the oven.

From my understanding, the quicker, and colder you can get the boolit, the harder it will be.

My question. If I put about a quarter cup of picking salt in my 5 gallon bucket of ice, I'm pretty sure I could get the water temp to roughly 14 degrees F (-10 C)

Would that additional temp help get a harder boolit? And the big, kicker, would the ions in the water screw with the lead?

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[Yodogsandman]

I wouldn't consider the BHN gain (if any) worth putting any salt in my barrels. If you just have to, use an anti-freeze solution.

[Rcmaveric]

When you drop from the mold into the water. Then put back into the oven. You just annealed the bullets. You can skip that step.

You are right. Also a mount of time backed can affect end BHN. Take a look at the heat treating article at LASSC. It compares time to water temp quench. 30 maybe attainable with the right alloy. I have no experince, try it and see what happens.

No experience with thay cartridge so i can not recimmend a BHN.

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[M-Tecs]

http://www.lasc.us/Kelter_Heat_Treat.pdf

[JonB_in_Glencoe]

14º F
That sounds like a great experiment. I hope you keep good notes and report them here, I've love to know the results.

I just used cold tap water (about 55-58º) and got 94-3-3 to 24-27 BHN
http://castboolits.gunloads.com/show...671-Heat-treat

[popper]

Add 2% Cu to 4% Sb, water drop in ice water and you get ~36 BHN. Size as soon as you can after W.D. About the same as SuperHard alloy.

[nhyrum]

Add 2% Cu to 4% Sb, water drop in ice water and you get ~36 BHN. Size as soon as you can after W.D. About the same as SuperHard alloy.

So an alloy of 2 percent copper, 4 percent antimony, if my chemistry memory is correct, 94 percent pure, soft lead? Or two percent copper for every 4 percent antimony?

My current alloy is wheel weights, so I could add 2 percent copper, and get a bhn of 36? Would the copper help reduce brittleness? Would copper pipe or wire work?

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[Outpost75]

No benefit to using ice water vs. ordinary cold tap water.
Some benefit to cold soaking in freezer after removal from the water quench.

[JonB_in_Glencoe]

So an alloy of 2 percent copper, 4 percent antimony, if my chemistry memory is correct, 94 percent pure, soft lead? Or two percent copper for every 4 percent antimony?

My current alloy is wheel weights, so I could add 2 percent copper, and get a bhn of 36? Would the copper help reduce brittleness? Would copper pipe or wire work?

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http://castboolits.gunloads.com/show...SO4&highlight=

[nhyrum]

http://castboolits.gunloads.com/show...SO4&highlight=

Perfect. Finally, a use for my soft lead. I have been debating about just tossing all the stick on weights I get. But, I'm going to start casting for 9mm soon too, so that will go through it quick

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[popper]

alloy of 2 percent copper, 4 percent antimony, if my chemistry memory is correct, 94 percent pure, soft lead Yup but size as soon as dry from WD. I add a known amount of tin or zinc, add copper sulfate for the Cu - it replaces the Sn or Zn. You could go to 4% but Sb MUST be 2x the Cu. They are NOT brittle. 2% casts fine for my 30 cal. rifle.

[nhyrum]

alloy of 2 percent copper, 4 percent antimony, if my chemistry memory is correct, 94 percent pure, soft lead Yup but size as soon as dry from WD. I add a known amount of tin or zinc, add copper sulfate for the Cu - it replaces the Sn or Zn. You could go to 4% but Sb MUST be 2x the Cu. They are NOT brittle. 2% casts fine for my 30 cal. rifle.

In the post he also mentions adding 1/4 of a penny /lb. I know they're mostly zinc, but would the copper melt in and in the correct proportion?

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[Yodogsandman]

Skip water dropping from the mold, oven heat treating for an hour in the oven is sufficient, before quenching. The faster the bullets drop in temperature the better. So quench quickly.

I use COWW and add 1% pewter. Food service grade pewter has a small percentage of copper (4-6%). Oven heated for an hour at 450*F and quickly quenched in ice cold water yields results at 30 BHN after 5 days of age hardening.

If you think you need more than 30BHN, you might look for other minor refinements for improvements.

[nhyrum]

Skip water dropping from the mold, oven heat treating for an hour in the oven is sufficient, before quenching. The faster the bullets drop in temperature the better. So quench quickly.

I use COWW and add 1% pewter. Food service grade pewter has a small percentage of copper (4-6%). Oven heated for an hour at 450*F and quickly quenched in ice cold water yields results at 30 BHN after 5 days of age hardening.

If you think you need more than 30BHN, you might look for other minor refinements for improvements.

I just don't know what else to do with the bullets! I'm worried if I drop them on a pile of other bullets, they'll get all dinged up.

If I need much harder than 30bhn, I got a copper solid I can use, but it can't get pushed as fast because it's bigger, being less dense copper and not lead. Recovered one I shot at a steel plate. Still weighs 300 grains, and only has a slight ding

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[Yodogsandman]

I dump my boolits onto a folded, old bath towel and roll them forward after each cast either with the sprue whacker stick or just lifting the front of the towel. They never get dropped on each other.

What problem are you experiencing that you need such a super hard bullet?

[nhyrum]

What problem are you experiencing that you need such a super hard bullet?

Mainly bear. That's really the whole purpose.

Just wanna make sure it gets through what it needs to to get to the important stuff that will stop it

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[popper]

Extremely small amount of copper in a penny. You must break them up before putting in pot for them to melt easily. Zn WW are easier to use.

[RED BEAR]

Never got to 30 gun but I've ice
water dropped wheel weights with extra 1% tin are coming out at 26 - 28 bhn for me. Just make sure there are no stick on in the mix.

[nhyrum]

Extremely small amount of copper in a penny. You must break them up before putting in pot for them to melt easily. Zn WW are easier to use.

Will the copper melt?

Also, how much zep per lb of lead for 2%? You say you added 2 tablespoons to 5 lbs lead, but it was soft?

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