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View Full Version : Lee Hardness Tester . . .calibration chart.



OFFSHORE
09-04-2018, 07:14 AM
A couple weeks back I came across and old post using the search function, I wanna say it was in 2011 of the post. . .now I can't find it. In the post it talked about the chart that comes with the Lee tester for the given readings not being "totally spot on" and one of the forum members did a more extensive series of tests and came up with a more accurate chart. Then another member in the post checked the new chart numbers and he agreed that the new hardness chart was definitely more accurate. He also offered to PM anyone the re-calibrated chart. Does anyone recall this post. . .have the revised chart or can point me in the right direction. I feel my Lee Tester is good/close enough for my hobby, but curiosity is getting the best of me and I want to do a comparison of my own. Thank you.

Merc41
09-04-2018, 09:07 AM
Hi Offshore.....here is an article I found...hope this is it: http://castboolits.gunloads.com/showthread.php?165698-Lee-Hardness-Tester-re-calibration

Let me know....

mdi
09-04-2018, 11:17 AM
My Lee tester is not laboratory accurate and it isn't necessary. Way too many variables to get "certified" hardness results from a mass produced tool that one "eyes" a dent in a sample. My bullet alloy needn't be accurate to 1 BHN of a laboratory certified as it just needs to get me a rough idea how hard my alloy is. A fourteen or a twelve ain't a lot of difference when cast, sized, lubed then shot out of my gun at 1,000 fps...

Dieselhorses
09-04-2018, 11:23 AM
I mic the dimple and never go wrong :coffee:

OFFSHORE
09-04-2018, 03:47 PM
Hi Offshore.....here is an article I found...hope this is it: http://castboolits.gunloads.com/showthread.php?165698-Lee-Hardness-Tester-re-calibration

Let me know....

Merc41,

You are Da Man! Yes, that is the exact post I was looking for and I have just sent a PM to Montana Charlie. Thank you very much.



My Lee tester is not laboratory accurate and it isn't necessary. Way too many variables to get "certified" hardness results from a mass produced tool that one "eyes" a dent in a sample. My bullet alloy needn't be accurate to 1 BHN of a laboratory certified as it just needs to get me a rough idea how hard my alloy is. A fourteen or a twelve ain't a lot of difference when cast, sized, lubed then shot out of my gun at 1,000 fps...

I totally agree with you, it's just a fun hobby for me and the critters I shoot aren't going to know whether they were shot with a 12 BHN bullet or a 20 BHN bullet. I just have a few things I'm curious about and I need to satisfy that. Maybe this info will do that.

dimaprok
09-04-2018, 04:00 PM
To throw another curve ball my lee microscope tool wasn't calibrated properly for a different reason, it suppose to have some kind of thread locker inside where the lens resides but mine was loose and when I used scanner to scan a batch of bullet dimples in ultra high resolution and measure precisely the dimple diameter size with photoshop and than calculate BHN value based on Lee chart I was able to go back and re-calibrated the scope to match that value. Something to think about, if you lens is loose inside you could be reading off because of that.

Merc41
09-06-2018, 12:36 PM
Glad to help Offshore...good luck.

Boogieman
09-06-2018, 05:39 PM
EasyCalculation.com has a free online Bh calculator You enter the ball dia. the load, and the indent dia. It does the rest

tankgunner59
09-08-2018, 11:34 AM
I have considered getting a Lee Hardness kit in the past, but first of I'm on very limited funds and like said above I'm not too concerned about a 1 BHN difference. So I use the old school method of water dropping and a thumbnail dent. It has always worked well so far. :grin:
Not that I disagree with those who have and use a hardness tester, I would if I had the funds, but like everyone else I do what I can with what I have. Awesome read for the future when I break into my piggy bank. [smilie=w:

Grmps
09-08-2018, 12:42 PM
make sure the surface is a smooth as possible, search the forum and build a simple scope holder, have a good light source. makes life soooooo much easier

https://www.google.com/search?q=Lee+Brinell+Hardness+Tester+expanded+BNH+ readings+%26+chamber+pressures&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiIk7-47KvdAhUHxVQKHVUkDJwQ_AUICigB&biw=1920&bih=894&dpr=1#imgrc=r_kfnqENCJUY_M:


https://i.imgur.com/Pn4xwTl.png

Dieselhorses
09-09-2018, 11:36 AM
Grmps, that's the chart I have printed out and use. Building a scope holder is an excellent idea also- basically almost the same of what I do (I use a magnifying glass).

I know this is probably old news but I'm telling it again LOL. There are a few machine shops where I work and I had fellow make me a simple steel rod with a 5/32" ball on the end he cut. I tighten this up in my drill press and place a cheap bathroom scale on under it. Place whatever I want to test on top scale and run it down (drill is not of course) to get 60 lbs. and hold for 30 seconds. Then I retrieve magnifying glass and caliper and fight to hold still enough to take an accurate reading. It isn't PERFECT but it gets me very close! (I also learned how to calculate using the original old school formula but the latter is quicker.)

Going to get me one of those desktop magnifiers with light built in to free up a hand.

OFFSHORE
09-11-2018, 08:55 PM
Grmps,

That is perfect. Again, you never cease to amaze me! Thank you, Sir.

RED BEAR
09-22-2018, 08:50 PM
you might try scanning the dent onto your computer ( at the highest setting ) then you can use. gimp ( free photo program ) or some other photo program to measure the dent . very accurate and a lot easier than the microscope. got this little trick off this forum can't remember who to give the credit to but it really is a neat little trick.

JBinMN
09-22-2018, 09:31 PM
Since I got my Lee tester a while back, I have been using a red marker to highlight the dimple & then use a calipers to measure it to get the diameter. Then compare to the chart.

Much easier than the "scope" provided.

Very simple.

G'Luck!
:)