Bhn question

[pearcetopher]

Hi guys

After measuring the bhn I got from the boolits I made last week I got some strange lee hardness measurements

It seems my water quenched range scrap is sitting at 22 bhn

My water quenched 50/50 scrap and wheel weights is sitting at 27 bhn

Doesn't this seem a little on the strong side ?
My tester has always given higher readings than it should...

[44MAG#1]

I would check some alloy of a known hardness and see what the tester said then. Kinda like "calibrating" (I know that is the wrong term but it is what I am using and hope that intelligent people know what I mean) it.
Then again if they shoot well what does it matter.
I wouldn't give a whoop as long as they shot well.
Over thinking to me.

[44man]

Something is wrong for sure. Neither one of those alloys should read that hard.
50-50 needs oven hardened to reach 18 BHN. My water dropped WW boolits will be 20 to 21.
The only question is "range scrap?"
BHN is a tricky reading anyway, just a metal percentage change can affect how a dent is made.
I like the LBT hardness tester best but never depend on readings for shooting anyway.

[Larry Gibson]

You need to "calibrate" the Lee against some pure lead as mentioned. It should give a BHN of between 5 - 6 with lead and closer to 5 BHN with certified pure lead.

I don't really see much wrong with those BHN readings. It appears the "range scrap" you have has a large % of antimony in it. If there is an error (assuming the Lee is calibrated correctly) and you are only taking one measurement then it may be that the sample number is too small. Use at least 3 measurements of each alloy, preferably 5+ and average them for a closer average BHN.

Larry Gibson

[JonB_in_Glencoe]

was the water temperture room temp? or ice water ?
you know as you cast and drop, the water will get warmer and the results can vary.

Also, did you add any shot to your range scrap ?
Jon

[geargnasher]

You need to "calibrate" the Lee against some pure lead as mentioned. It should give a BHN of between 5 - 6 with lead and closer to 5 BHN with certified pure lead.

I don't really see much wrong with those BHN readings. It appears the "range scrap" you have has a large % of antimony in it. If there is an error (assuming the Lee is calibrated correctly) and you are only taking one measurement then it may be that the sample number is too small. Use at least 3 measurements of each alloy, preferably 5+ and average them for a closer average BHN.

Larry Gibson

I think so, too. You can calibrate the Lee tool with a good bathroom scale.

My water-dropped 50/50 clippy/PURE plus 1% tin always ages to between 19 and 23 BHN in a month, depending on caliber and mass of the boolit.

Gear

[mdi]

I agree with the "calibrating/comparison" posts above. Since the Lee process involves human input (hand pressure on a lever for a specific time) results can vary, BTDT. . Another difficulty is measuring the indent, lost of judgment goes there for matching two lines with a round dent. I have had to be extremely careful to be consistent to get good (realistic) measurements.

[pearcetopher]

ok so I had some lead balls from track of the wolf and I ran them through my tester

the hole it made was larger than my measurer, so I'd imagine the hole size is around 1.2, does this sound correct

[geargnasher]

Somebody here, long ago, posted a chart with extrapolated numbers for the Lee tool down past 7 BHN, wish I could find it now.

I don't think it's the tool as much as what's in your particular brew of range scrap.

Gear

[runfiverun]

arsenic..

[waco]

arsenic..

Did you just call me an ****?

[JonB_in_Glencoe]

Somebody here, long ago, posted a chart with extrapolated numbers for the Lee tool down past 7 BHN, wish I could find it now.

I don't think it's the tool as much as what's in your particular brew of range scrap.

Gear

http://www.texas-mac.com/sitebuilder/images/Extended_BHN_Chart_for_Lee_Tester3-728x491.jpg

[JonB_in_Glencoe]

arsenic..

That was my thought when I asked...

did you add any shot to your range scrap ?

[mdi]

I gave up on using the 'scope supplied with the Lee kit. Now I use my magnifier visor and dial calipers to measure indent. Works for me...

[bangerjim]

Never trust a "factory calibrated" anything!

1st thing I did when I received my Cabine tester was to check it against several known standards and had to tweak the spring adjustment a nudge. Not much, but it was off ~1 unit. And you need to do at least 3 test at different spots on the ingot (or 3 slugs from same batch) and average them.

That is what is so nice about the Cabine.....only takes 3 seconds for an accurate read!

FYI........I have found out you do NOT need to hold the Lee thing for 30 seconds. A slow "bump-n-go" that brings the plunger even with the top is all that is needed. That is based on compared readings with Cabine & Lee. I have both and did several tests.

banger

[Alstep]

Here's a site for easy calculation of BHN
http://easycalculation.com/physics/classical-physics/brinell-hardness.php