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GregLaROCHE
08-17-2018, 12:48 PM
I finally got to use my new Lee hardness tester today. It was a little tricky to use that scope. I finally made a stand for it from a clear Tupperware container. It got easier after that, but I still need more practice.

I found my range scrap ingots averaged BHN 9.8, but was surprised that my cast, water quenched boolits (405 gr.)from maybe five months ago tested at 18.6 BHN. Does that make sense that they could havé hardened that much or do I need more practice?

Also, I measured a pure lead ingot and it was just past markings in the scope. When I looked at their table, it doesn’t go near that high. Does that mean you can’t measure pure lead with it?

I am very interested to hear what others think.

Thanks

daloper
08-17-2018, 12:59 PM
Before you test it color the spot that you are going to read with a blue or yellow hi lighter. This makes it mush easier to see the indent. Color the spot before you press the indent. Not sure if I am making my self clear.

Grmps
08-17-2018, 01:13 PM
did you file the surface flat and smooth before testing?

search Lee hardness tester in the google search bar at the top right of this page.

Water quenched boolits (COWW) can easily reach over 25 bhn depending on the amount of antimony and arsenic (speeds up hardening) in the alloy

search water quenching

Rcmaveric
08-17-2018, 02:18 PM
There are extended Lee hardness charts you can google up.

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jimkim
08-17-2018, 04:37 PM
My best advice, is to build something to hold the bullet, and the scope. You can use a cheap microscope and calipers to measure the dent too. https://uploads.tapatalk-cdn.com/20180817/a6af23a94caf5048ffc099bca4a7145f.jpghttps://uploads.tapatalk-cdn.com/20180817/a04b8c14b6c4fc28c0d11d968e537e61.jpghttps://uploads.tapatalk-cdn.com/20180817/5036cc649e47d05b38a14a5acdda3095.jpg

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Harry O
08-17-2018, 11:13 PM
I have an extended hardness sheet for the Lee hardness tester that goes down to 5.0. How can I post an Excel spreadsheet here?

Harry O
08-17-2018, 11:28 PM
Lets try this. Print it out and turn it sideways.

225639

GregLaROCHE
08-18-2018, 03:41 AM
My best advice, is to build something to hold the bullet, and the scope. You can use a cheap microscope and calipers to measure the dent too. https://uploads.tapatalk-cdn.com/20180817/a6af23a94caf5048ffc099bca4a7145f.jpghttps://uploads.tapatalk-cdn.com/20180817/a04b8c14b6c4fc28c0d11d968e537e61.jpghttps://uploads.tapatalk-cdn.com/20180817/5036cc649e47d05b38a14a5acdda3095.jpg

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Wow! Those are some real pro setups. I’ll have to find thr time to build something tike one of those

William Yanda
08-18-2018, 07:18 AM
I would be interested to know if boolets made from your alloy tested the same as the ingots. I have the impression-don't know where it came from-that because of the size difference affecting the cooling rate that there might be a difference.
Respectfully

mdi
08-18-2018, 10:55 AM
I don't consider my Lee hardness tester to be "laboratory accurate" and it just gets me in the ball park. I use mine to give me relative hardness, to be able to repeat an alloy that works good for me. I made a holder for my 'scope, but still didn't like it so I just use my magnifying visor and my dial calipers to measure the indent. Works for me....

Harry O
08-18-2018, 07:42 PM
I would be interested to know if boolets made from your alloy tested the same as the ingots. I have the impression-don't know where it came from-that because of the size difference affecting the cooling rate that there might be a difference.
Respectfully

My experience is that an ingot is ALWAYS softer than a bullet. My guess, like you, it is because of the cooling rate. The lighter the bullet, the harder it is. One time I cast two different bullets (alternately) from the same melt at the same time. One was about 200gr and one was about 100gr. The smaller bullet was consistently one Bhn harder than the larger bullet.

GregLaROCHE
08-19-2018, 04:42 AM
Lets try this. Print it out and turn it sideways.

225639

Could you send that chart in a different format. I can’t seem to be able to manipulate it to get anything,but a small chart on a black back ground. Maybe a PM or the site you got it from.

Thanks

Harry O
08-19-2018, 03:06 PM
Could you send that chart in a different format. I can’t seem to be able to manipulate it to get anything,but a small chart on a black back ground. Maybe a PM or the site you got it from.

Thanks

The original document is in Excel on my harddrive (I made it myself). I could not copy, upload, or paste it here. I was able to post that one by saving the Excel spreadsheet in jpg and upload/post it that way. If anyone can PM me instructions on how to post an Excel spreadsheet here, I would appreciate it.

Camper64
08-19-2018, 04:32 PM
Here is a PDF version of the excel spreadsheet.

225748

Rcmaveric
08-19-2018, 04:49 PM
Lets try this. It is my template and reference file. First tab is the extended Lee hardness chart.
https://1drv.ms/x/s!AimSFPgvHa-5gqZJim5qP83_7gzfzA (This is the Excel File)
https://1drv.ms/b/s!AimSFPgvHa-5gqZLsoe76EiGepF60Q (This is just a PDF of the Lee hardness Chart)

Hope i posted those right. Darn newfangled technology.

mehavey
08-19-2018, 06:56 PM
https://s33.postimg.cc/w3puhgzcf/BHN_Chart4.jpg

FWIW: I have discovered that truly pure lead (reactor shielding) is BHN <4.5 (not 5.0 as internet lore would have you believe)

For that matter, "...as published on the Internet..." will invariably state as "settled science" that well-known alloys are harder than they really are.

Take you own data....



(Incidentally, the Lyman#2 and 30:1 readings are Rotometals Foundry alloy)

GregLaROCHE
08-20-2018, 01:53 AM
The PDF table printed out fine. Thanks. The information from others is interesting too. I wish there were a chart with the change In hardness over time. I guess you would need one for each alloy.

Thanks to everyone for your help.

William Yanda
08-20-2018, 03:27 PM
My experience is that an ingot is ALWAYS softer than a bullet. My guess, like you, it is because of the cooling rate. The lighter the bullet, the harder it is. One time I cast two different bullets (alternately) from the same melt at the same time. One was about 200gr and one was about 100gr. The smaller bullet was consistently one Bhn harder than the larger bullet.

That's neat to know. Thanks for the info.

Camper64
08-20-2018, 04:13 PM
Here is link that will download the Lead Alloy Calculator.

225829

W.R.Buchanan
08-20-2018, 04:45 PM
I don't consider my Lee hardness tester to be "laboratory accurate" and it just gets me in the ball park. I use mine to give me relative hardness, to be able to repeat an alloy that works good for me. I made a holder for my 'scope, but still didn't like it so I just use my magnifying visor and my dial calipers to measure the indent. Works for me....

MDI This makes it Laboratory Accurate. (See Pic)It's all about how close you can measure the indent. You do several tests and then average them. If you use a comparator your results should be within a tenth and with interpolation of the chart you can get really close to the actual BNH. But due to minor variations you need to do an average.

The kicker on the Lee Comparator is that the hash marks are .002 apart. Thus a higher degree of "Interpolation" is necessary than if you use a more sophisticated instrument to measure.

The Penetrator is going to do the exact same thing every time as long as you can get the Ram to displace the same amount every time which compresses the spring the same amount. That requires that the Ram be even with the top of the die to the same point every time. This is a place where deviations can occur.

A way to eliminate this variable would be to set the die up in your press so that the press is going over center or bottoming out when the ram hits TDC.(Even with the top of the die) That way you are doing the same thing every time.

Another way would be to attach a dial indicator to the ram and run it up to zero every time.

If you can get the "Penetrator" to repeat which it should since it is only compressing a spring. Then the only other variable is the actual measuring of the indentation. If you can get that to repeat then you are back to Lab Quality Analysis. All that would be left is calibration to a known standard.

Randy

GregLaROCHE
08-20-2018, 05:30 PM
The one question I have is when I file a flat spot, there’re a lot of hash marks from the file. I don’t want to use my smaller jewelers files. It’s already a chore to clean the coarser ones. Maybe some 200 get sandpaper after the file would help.

RedHawk357Mag
08-23-2018, 10:11 AM
Before you test it color the spot that you are going to read with a blue or yellow hi lighter. This makes it mush easier to see the indent. Color the spot before you press the indent. Not sure if I am making my self clear.Thank you. Simple step definitely helps. Two thumbs up.

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