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Jeffjmr
07-01-2017, 11:09 PM
Enjoying my new Lee Hardness tester. I am finding it remarkably consistent when I follow the instructions carefully.

Strangely, though, I found no difference in hardness of one of my alloys between air cooled and water dropped. I tested them very shortly after they cooled. Could this have been a factor?

I used three samples of each, all of which tested identically. It was alloy given me by a friend, among the softest I have around 13 BHN according to the Lee Chart. I used ice water, and let them sit in the water for about 5 minutes.

My pure lead tests at something less than 8 since that is the lowest the Lee chart goes to, and my magnum shot alloy tests at 28, so I think the tester is pretty close.

Did I do something wrong? Perhaps the water drop difference doesn't show up until the boolits age a bit?

Thanks,
Jeff

OS OK
07-02-2017, 12:04 AM
198911

See the red marks-A-lot on the cast that I dimpled with the Lee BHN tester?

It makes it very easy to see the perimeter of the dimple under magnification.

Sounds like you have it down pat, but in case you have old eyes like this old fart the red surely helps.

Here's an expanded chart for the Lee tester...

http://r.search.yahoo.com/_ylt=A0SO8wTPblhZoAYA2OZXNyoA;_ylu=X3oDMTByYnR1Zmd 1BGNvbG8DZ3ExBHBvcwMyBHZ0aWQDBHNlYwNzcg--/RV=2/RE=1498996560/RO=10/RU=http%3a%2f%2freloadingtips.com%2freviews%2flee_ bnh_chart.htm/RK=1/RS=Wqn4C.56ZPQo2nFnIerYdkFntU4-

I found it on this search...

https://search.yahoo.com/search?ei=utf-8&fr=aaplw&p=LEE+BHN+tester+extended+chart

jcren
07-02-2017, 12:21 AM
Lead needs a crystiline additive to water harden. Antimony and arsenic are commonly used to allow quench hardening in lead.

crackers
07-02-2017, 08:23 AM
See the table
http://www.lasc.us/heattreat.htm

Calamity Jake
07-02-2017, 11:56 AM
Enjoying my new Lee Hardness tester. I am finding it remarkably consistent when I follow the instructions carefully.

Strangely, though, I found no difference in hardness of one of my alloys between air cooled and water dropped. I tested them very shortly after they cooled. Could this have been a factor?


My pure lead tests at something less than 8 since that is the lowest the Lee chart goes to, and my magnum shot alloy tests at 28, so I think the tester is pretty close.

Did I do something wrong? Perhaps the water drop difference doesn't show up until the boolits age a bit?

Thanks,
Jeff

Use your 13 BHN alloy and run your test again but let the boolits age for two weeks before hardness testing.
You should see a big difference.

Jeffjmr
07-02-2017, 03:42 PM
Thanks all. I surely expect the aging related hardness. What surprised/disappointed me was the lack of difference between the water dropped and air cooled. I'll age them then test again.

But if I read you correctly, pure lead for example would NOT show a change with water dropping, but moderately hard alloys to start with would see a larger differential?

Jeff

gwpercle
07-02-2017, 05:18 PM
Thanks all. I surely expect the aging related hardness. What surprised/disappointed me was the lack of difference between the water dropped and air cooled. I'll age them then test again.

But if I read you correctly, pure lead for example would NOT show a change with water dropping, but moderately hard alloys to start with would see a larger differential?

Jeff

Correct. Antimony and Arsenic must be present in the alloy, as found in clip on wheel weights, for it to quench harden.
A boolit alloy of just lead and tin will not quench harden. The Antimony seems to be the magic ingredient for quench hardening.

If you do quench harden, sizing the bullet will work soften the boolits surface and you will loose some of that hardness. The hardest boolits are obtained buy sizing, heat treating and then water quenching.
Gary

ichthyo
07-02-2017, 06:33 PM
Thanks for sharing. I always water quench, but don't have a hardness tester. I usually cast with 50:50 clamp on wheel weights\stick on WW. Do the stick ons contain any antimony?

gwpercle
07-02-2017, 06:54 PM
The charts I have indicate stick on weights are 100% lead with a bhn of 5. I have always treated them as pure lead. The 50 / 50 clip on / stick on is my favorite alloy for handgun boolits, I just air cool them and let them age harden. It also works for rifle with a good lube .
Glad to help,
Gary

ichthyo
07-02-2017, 09:24 PM
Thanks Gary. I often powder coat my handgun boolits, but it may not be necessary. I don't cast rifle calibers.

mdi
07-02-2017, 09:49 PM
FWIW; I had trouble with Lee's microscope so I used my magnifying visor and calipers. I make the indent as usual and use the visor and measure the dent with my calipers. With little practice (and a strong light) I'm more accurate and repeatable...

As to your question about hardening, I'd suggest you consider adding some
arsenic to your alloy...

Yodogsandman
07-03-2017, 03:52 PM
Thanks for sharing. I always water quench, but don't have a hardness tester. I usually cast with 50:50 clamp on wheel weights\stick on WW. Do the stick ons contain any antimony?

http://castboolits.gunloads.com/showthread.php?229666-Stick-On-WW-XrF-Data

243winxb
07-04-2017, 08:09 AM
Lyman - Heat Treatment of Cast Bullets to Harden Them
Q: Is there anything I can do to make the bullets harder?
A: Cast bullets can be heat treated to increase their hardness providing your alloy has some antimony present. To heat treat your bullets: Cast your bullets in the normal manner, saving several scrap bullets. Size your bullets but do not lubricate them. Place several scrap bullets on a pan in your oven at 450 degrees and increase the temperature until the bullets start to melt or slump. Be sure to use an accurate oven thermometer and a pan that will not be used again for food. Once the bullets start to melt or slump, back off the temperature about 5 to 10 degrees and slide in your first batch of good bullets. Leave these in the oven for a half hour. Remove the bullets from the oven and plunge them into cool water. Allow them to cool thoroughly. When you are ready to lubricate, install a sizing die .001" larger than the one used to initially size them. This will prevent the sides of the bullets from work-softening from contact with the sizing die. Next apply gas checks if required and lubricate. These are now ready for loading.

2% antimony is needed to work. Full hardness in about 2 weeks.

Yodogsandman
07-04-2017, 02:37 PM
Better to heat soak boolits for at least a full hour in the oven.

popper
07-04-2017, 02:52 PM
Yes, oven soak for an hour. You're depending on solid mobility of atoms to set the crystal structure, that takes time. Wd from mould is going through the solidification - it's already 'soaked'. As speeds up hardening, ~ 0.1% will do. PC or HiTek baking removes any WD hardness so do the soak and WD to regain hardness. Or AC a harder alloy.

Edward
07-04-2017, 03:12 PM
My lead ,w/w alloy goes from mold to bucket of water and starts to harden in 1 week and stabilizes in 2 doing nothing else ,depending on ratio that could go from 10-12 to 23 BHN ,at least at my house . Boolits do not last to see what happens a year from now.

byrd45900
07-13-2017, 04:38 PM
Wow,some great info on this post!Thanks every one!

44MAG#1
07-13-2017, 05:46 PM
If you have an alloy that will respond to oven heat treating they will also water quench from the mold.
Either your alloy is not a respondable alloy to heat treating or you are doing something wrong. Any alloy that is worthy of oven heat treating or water quenching from the mold will do most of their hardening within 48 hours. Any more time will add some hardness but not a great amount of hardening
If you have arsenic and antimony present the alloy will harden. Drop your bullets from the mold just as the sprue hardens enough to not smear the top of the mold. NO COOLER. just solid enough to prevent smearing IS ALL.
The COOLER the bullet is from the mold the less hard it will get.