Lead Hardness Tester

[cat1870]

Just wondering what you all used for a lead hardness tester.
I've used the LBT for years and recently bought one from ST Machining .
I Like them both but have compared the 2 using the same bullet [b](I cut off a 1/8" of the bullet between tests)[/b] and find them about reading off with the LBT measuring 1 or 2 readings higher than the ST.

[powderburner]

I have an old cabine tree and an lbt. They both read slightly different with the same bullets. ( I use different ones each time) but they are always within the range of the brinell chart. And ingots register different than bullets but also within the same parameters.

[RB1Shooter]

I have a Cherry Tree. For pure lead ingot, the Brinell numbers are dead on. For pure tin ingot, the numbers are dead on also. I am very anal about mixing my lead and tin. I use both pure lead and pure tin mixing at 20:1, carefully weighing each. Also, the only material I have ever melted in my pot is pure lead & pure tin.

After casting bullets and letting them cool for 3 days, the numbers typically reflect a 25:1 hardness. Weighing 5 ea. and averaging. Over time, EG: setting undisturbed, 4 month's over the winter, they will harden to the point of approaching 20:1 but never quite get there.

Why the difference? My guess is, the point of the tester sets on the nose of the bullet. The nose of the bullet does not have the volumetric support of material on either side of the point as it would in an ingot. Consequently, when turning the point into the nose, the material is easier displaced giving a softer reading. I have cast an ingot using a 20:1 from same mixture I cast bullets. The hardness of the ingot, 3 days later, centers around 20:1

That's my experience.

[RB1Shooter]

Sorry "Cabin Tree", not "Cherry Tree".

[steveu834]

I use the Lee tester. It works as well as the other ones, just a little more difficult to use. I use the top part of a plastic water bottle with a hole in the lid to hold the microscope still.

[kwilliams]

To get a reliable and consistent dial hardness value, you need to have the exact same size ingot sample every time. Random clipping of a bullet nose or filing a flat will never offer repeatable results. A separate core mold that produces 2 smooth flat ends is what is needed on the Cabin Tree tester.
kw

[RB1Shooter]

My bullet noses are flat, .180 metplat and of course the base flat also. I have also used the raw sheet lead to compare against a cast ingot of same and got the exact same results. Like I said, I see bhn consistency from each of the 5 bullets I test. They are consistent 3 days after casting and 4 months after casting. What I don't see is a match between bhn readings vs published mix ratio numbers. IE: readings of 25:1 vs a careful mix of 20:1 lead.

Patience and being careful are the key when taking measurements. Plus, regardless if the mix is 20:1 and the readings indicate 25:1, if the bullet shoots accurately without leading, you have what you want. Then casting repeatability becomes the issue.

"There are no shortcuts in match BPCR shooting"