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BulletFactory
03-09-2011, 09:00 PM
I was casting some, and got to thinkin', has anyone tried to quench the bullets in a pot of boiling water? When I water drop, the BHN goes from 8.7 (air cooled), to almost 30 in a few days, so, I thought that maybe dropping them into boiling water might not make them as hard. I'll try a batch and test them out ofer the next few days to see how it comes out.

11B-101ABN
03-09-2011, 09:55 PM
Try used motor oil. I'm no authority, but worked maintenance in a heat treat shop for a few years, and almost every furnace had TWO quench tanks...one water and one oil. I once asked one of the heat treaters why and he said "Sometimes water quenches too hard".

BulletFactory
03-09-2011, 10:01 PM
What would be the chances of a flash fire?

HangFireW8
03-09-2011, 10:27 PM
Try used motor oil. I'm no authority, but worked maintenance in a heat treat shop for a few years, and almost every furnace had TWO quench tanks...one water and one oil. I once asked one of the heat treaters why and he said "Sometimes water quenches too hard".

O1 is Oil Hardening tool steel stock.

W1 is Water Hardening tool steel stock.

Use the right quench for the given stock.

MtGun44
03-09-2011, 11:35 PM
Probably little difference, but run the experiment and report back. cheap and easy
way to gather knowledge.

Bill

bhn22
03-09-2011, 11:38 PM
Air cool them, and adjust your alloy accordingly.

BulletFactory
03-10-2011, 12:34 AM
I don't have a budget that allows that.

Ole
03-10-2011, 12:36 AM
Cut your alloy with equal amounts of pure lead.

My 50/50 WW/PB water drops around 15-18BNH, which is just about perfect for most of my general purpose needs.

stubshaft
03-10-2011, 12:37 AM
Water dropping then annealing will probably give you more consistent results.

KYCaster
03-10-2011, 12:40 AM
Very interesting........

I suspect you may see a substantial difference.

May I suggest an additional test while you're at it? After your casting session, remove some of the boolits from the boiling water so they will cool faster to room temp., and leave the remainder in the water, turn off the heat and let them cool slowly with the water.

Oh....and don't forget the control groups.....air cooled and quenched with your usual method.

Good luck
Jerry

BulletFactory
03-10-2011, 01:28 AM
Start alloy BHN 8.7

Air cooled .................... Quenched
Day 1 8.7.................... 13.4
2 8.7.................... 22.7
3 7.8.................... 28.5
4 8.7.................... 27.2
5 8.7.................... 29.9
6 9.2.................... 29.9
7 8.7.................... 28.5
8 9.2.................... 28.5
9 8.2 .................... 28.5
10 8.5.................... 29.9
11 8.2.................... 29.9
12 8.5.................... 28.5
13 8.2.................... 29.9
14 8.2.................... 29.9
15 8.2.................... 33.0
16 8.2.................... 29.9

waksupi
03-10-2011, 02:10 AM
You can vary the heat in an oven in around 25 degree increments, and make boolits pretty much any hardness you want. Make a chart, and you will know what you are hardening to with each batch of similar alloys.

chris in va
03-10-2011, 02:47 AM
Are these WW alloy?

Bret4207
03-10-2011, 07:31 AM
BF, what is your alloy? I find it puzzling that such a soft alloy hardens so much. My AC WW goes from about 9 hot to about 11.5 after 2 weeks, when quenched it genrally ends up around 22-24. Just what do you have there? And what are you measuring with, what are you using for samples?

44man
03-10-2011, 10:34 AM
BF, what is your alloy? I find it puzzling that such a soft alloy hardens so much. My AC WW goes from about 9 hot to about 11.5 after 2 weeks, when quenched it genrally ends up around 22-24. Just what do you have there? And what are you measuring with, what are you using for samples?
You hit the nail on the head. What in the world is the alloy? What does he measure with? That is so far out of the ballpark it is crazy!
Sounds like he has tool steel melted in his lead! [smilie=l:

BABore
03-10-2011, 10:47 AM
Likely bismuth.

1Shirt
03-10-2011, 11:36 AM
Agree with Bret and 44Man, Something just doesn't add up with the extremes.
What is your alloy? What kind of tester? I use a cabin tree, and I have never seen that much of a variable over time?
1Shirt!:coffeecom

Marlin Junky
03-10-2011, 12:09 PM
BulletFactory...

The most I've ever been able to harden a Pb/WW alloy through heat treating (above 500F and into ice water) has been just under 3X its air cooled hardness. Where did you get this mystery boolit metal and with what are you measuring its hardness?

MJ

BulletFactory
03-10-2011, 12:31 PM
I'm using a LEE tester. I got the alloy from an old guy who owns a gunsmithing shop that has been around for decades, so I figured he knew what he was doing. I'm not sure exactly what's in it, but he told me that it was like 80% shot, and that it has a lot of arsenic in it. I was having trouble getting it to fill out, so I added 2 pounds of a 95/5 solder for tin, in 50 pounds but the only way to get it to fill out is to run the pot at 825 to 850*F. I get a lot of air pockets, and quite often the bases do not fill out. There are thise little bits and pieces of **** that I can't seem to flux out, the bullets never come out shiny, and they often will have these little splotches on them. I have to cast 250 to 300 rounds in order to get 100 good ones.

sqlbullet
03-10-2011, 12:51 PM
Isotope lead of the kind Muddy Creek Sam sells behaves this way in my tests. Cast with 5-7 second sprue cooling cadence from a 750° pot and drop into cold water and I get above 30 on my Lee tester, average of 10 samples.

OP...These will soften with time. Two years later bullets that test 32 (10 sample average day after casting) were re-tested and came in at 24 (same ten sample average). I don't know what the time/hardness curve was.

Also, my tests show two other points of interest. Of the 180 samples in the original tests (18 groups of 10), all the samples that averaged a hardness below 23 were harder, and all the samples that averaged a hardness above 23 were softer. It seems this alloy is completely hardness stable only at a BHN of 23. However, the air-cooled hardness of the alloy is 10-12.

The air-cooled with no subsequent heat treatment were by far the least stable, averaging a 44% gain in hardness, followed by the water quenched, then annealed to remove hardness, at 24% average gain. These two samples started the furthest from the apparent magic number of 23.

These results are only minimally useful without more discrete time measurements. I need to repeat the tests and retest each sample lot each week, tracking the time component of the changes and to validate the results as repeatable.

My initial impression is that this alloy does have a 'stable' hardness and if you can find a way to hit that number, 23, then it likely won't change much over time. I also need to expand the tests to include other alloys to see if this is just an anomaly of this isotope lead, or if it is a general rule.

BulletFactory
03-10-2011, 12:55 PM
If I had 200 bucks, I'd just replace it with Lyman#2 and pitch this stuff.

MtGun44
03-10-2011, 02:58 PM
You need to cut that alloy with a LOT of plain Pb if it is mostly hard shot. Hard shot is used
as a 'seasoning' by most that have it, not as the primary alloy. You are casting bullets that
will be so hard as to actually be a problem unless they are absolutely perfectly fitted. I think
you need to trade out a pound of that alloy for 2 or 3 pounds of plain. 80% shot is pretty
useful as a hardener, but pure silly as a main alloy.

Bill

BulletFactory
03-10-2011, 03:33 PM
Why is the BHN so low? Air cooled, its 8.7.

Bret4207
03-10-2011, 07:06 PM
Well, Bill thinks the stuff is hard shot, I'm thinking you got a lot of real soft shot and maybe some bismuth or some of the other weird alloys they use now. The arsenic content being high I can accept. What a truly high arsenic content would do to your alloy I don't know.

I'm also wondering about your Bhn tester. The Lee system is not...easy to use I guess is the best word. I've done the ball indentation and measuring it with calipers and magnifying glass route. There are surely easier ways.

I don't know what all you have there, but for the headaches its giving you I'd trade it off to a sinker maker or someone looking to make anchors for his decoys.

excess650
03-10-2011, 07:28 PM
Arsenic is added to lead alloy in shotmaking to cause it to form spheres when dropped. Your fill out problem may be due to too much arsenic.

BulletFactory
03-10-2011, 08:13 PM
Hmmm, how do I deal with that? I was thinking zinc.

runfiverun
03-10-2011, 09:31 PM
arsenic does increase surface tension it is also a "catalyst" of sorts to react with antimony when quench treating lead.
you have a good alloy there, just too much of a good thing.
it woud make a good enrichment alloy.
i'd break down and get a box of ww's, some strap on weights, whatever, and save what you have as a helper.

BulletFactory
03-10-2011, 11:04 PM
Should I go half and half with WW?

Bret4207
03-11-2011, 07:42 AM
That would probably be a good starting place. I would melt a pound of WW and a pound of your alloy and see what it does. I wouldn't mix a big bunch together till you know what it does. You might need to go 2/1 or 3/1 WW to your alloy to get an easy to use product.

clintsfolly
03-11-2011, 09:36 AM
BulletFactory i am just up the road by Lansing if you want i can retest some of your samples with my Cabine Tree tester. If you need some WW to cut your rich alloy i maybe able to help too. Hope this will help. PM me if you want to. Clint

BulletFactory
03-11-2011, 10:48 AM
Could use any help I can get, my engine is going to blow soon, so I can't drive very far. Its getting loud.

JIMinPHX
03-11-2011, 11:45 AM
What would be the chances of a flash fire?

Yes.

When you oil quench, you need to have a bucket of oil that is big enough to absorb the heat from the quenched metal without the oil getting hot enough to catch fire. Heat treating in a small container of oil is asking for trouble. Dunking the part in the oil slowly is asking for trouble. I learned both those lessons the hard way.

JIMinPHX
03-11-2011, 11:49 AM
arsenic does increase surface tension it is also a "catalyst" of sorts to react with antimony when quench treating lead.


I was always taught that a catalyst was a material that either invigorated or moderated a reaction but did not otherwise change the properties of the reaction. I was always taught that the catalyst was never consumed in the reaction, but separated out when the reaction finished. That doesn't seem to quite match what I am understanding you to say.