Lee Hardness Tester - don't use on base?

[BHuij]

I just got a Lee BHN tester, and the instructions specify not to put the impression on the base of the bullet, as this will "result in a softer reading than the lead should show."

Anyone know why that would be?

Before reading that part of the instructions, I tested a couple of bullets that I cast from pure stick-on wheel weight alloy, expecting them to be in the range of 6-7 BHN. They came out to 8.7, using the base of the bullet. Does this mean my air-cooled SOWW alloy is actually harder than 8.7? Seems strange...

[Rcmaveric]

Your supposed to file a flat spot onto the bullet. Has to do with getting to whats inside the bullet. The skin of the bullet gives false readings about what the lead is really. Think it applies more to water dropping but it is easier to teach that than to explain nuisances and debate science and physics. As long as you file a flat spot and test that way. You will get a reliable and repeatable reading of what is a better representation of the bullets make-up.

Just because its a stick on doesn't mean its pure.

I am not sure how much i believe in my testers accuracy, but it is consistent. I was playing with math yesterday and did a mixing cross. Calculated that 2 parts of 8 BHN range scraps plus 2 parts of 12 BHN COWW would equal 10 BHN. I casted a bullets with it and it came out 10BHN. So i trust mine to create a consistent alloy.

Also, give it about a week before testing BHN. Gives it time to stabilize and/or equalize.

[bangerjim]

Pb alloy hardness is just a seat-o-the-pants reading anyway.

10.0 vs 10.5........who cares!

I have tested MANY boolits and alloy ingots with my Cabine Tree tester against my NIST tracable tester and it is VERY close. But as long as I read 10 (plus or minus 1) I am happy.

The alloy calculator on here is also very accurate.

Aging will shift alloys with Sb and Sn in them, so wait at least a week or two to pass judgement on your final boolit hardness.

The Lee tester has a lot of variables in the reading - lighting, eyesite, angle, filed flat, etc that can effect the reating you derive. Does it work? Yes.....if you have all the parameters the same each time and are good at reading the calibrated scale thru that teeny microscope. I prefer the digital dial readout on my Cabine tester. And it does not tie up my loading press.

Nice thing about the Cabine style tester is it can test ANY shape of Pb.....boolits, ingots, slabs, sheets, hunks......makes no difference. The Lee “thing” (I have one that I never use any more) must test boolits with a filed flat area. Not something I wish to always do. I take my Cabine tester on the road to the scrap yards to test alloys B4 getting an x-ray analysis by them. Tells me a lot about what I am buying.

But use what you have and/or can afford.

[Rcmaveric]

The Lee Hardness test works in the hand press and makes it portable. I can test about anything. I just hit it with some sand paper to make a flat spot. I used cardboard, dowels and hot glue to make a stand for the magnifying glass. Adapt and over come.

[fredj338]

You do not want to test the base because there may be an unseen inclusion. So it isn't softer but if not solid, your reading will be off.