BHN? Pencils vs. Lee Tester

[~JM~]

New guy here. Just performed my first smelt on Monday: https://castboolits.gunloads.com/sho...or-First-Smelt

I used the Art Pencils after the ingots had cooled & came up with somewhere between the 4B pencil & the 6B which would be in the 5-9BHN range.

Today (Wednesday) I tried the Lee tester. The results are much different with higher BHN numbers. My smelt was 2 batches of material. The first batch was material (shown in top half of this pic) that I suspected was softer.



The second batch was the sinkers.

Todays readings show the opposite. My first batch is reading in the .05 range, or 20BHN. The 2nd batch is reading .07 range, or 10BHN. Not 100% confident in my first effort testing skills.

Seem to recall that lead becomes harder after a certain time frame. Don't know the period of time. Lead storage temperature is in the 60 degree range at this time.

Interested in feedback. Thank you.

[Froogal]

I've never used the pencil method, but I have used the Lee tester. Basically it told me what I needed to know, but with a bit of guesswork.

[dannyd]

I use both methods to test the pencil is way easier than the Lee and works just as well.

[oley55]

I don’t know how long before ingots reach full hardness, but today I rechecked the hardness of an older batch of diver recovered saltwater weights and found they are considerably harder. Originally they were 4B/9BHN. Today the ingots are 2B/11-12BHN. It’s probably been 6 months since I smelted them.

I have compared known/expected hardness with drafting pencils and find them to be reliable enough for my needs, but have not compared them against a Cabintree or similarly regarded hardness testers.

[centershot]

Regarding your pencil testing, you should file a flat, smooth spot on the ingot, then test it there.

[Green Frog]

I’d be afraid to speculate on the composition of fishing weights (or “sinkers”) since the exact composition is of virtually no interest to the folks who cast them. On “recovered” sinkers, I wouldn’t expect any two to be the same alloy, since they were probably lost by different fishermen.

Froggie

[bangerjim]

Hardness is all ballpark! No method is dead on.

My rankings, in order of accuracy, repeatability, and price:

least accurate - pencils
accurate - Lee + very good eyesight & patience, lots of it!
Most accurate (& repeatable) - Cabine style tester with digital readout.

I have them all and have used them all extensively. I only use the Cabine tester now. I have checked (and calibrated) my Cabine tester against NIST tester standards and it is extremely accurate and 98% repeatable.

But today hardness is not as important as we once thought. "Fit is King" today. Make sure your boolits FIT your barrel properly by slugging the barrels!!

And if you PC everything you can shoot 8-12 hardness in just about anything, even 2,500 FPS rifles. PC gives you a hard smooth almost indestructible coating on the lead.

Pencils are probably good enough for what you are doing. Do not trust sinkers for repeatability in alloy!!!!!!!!!!

Cast away.

banger

[~JM~]

accurate - Lee + very good eyesight & patience, lots of it!

banger

...And the ability to move in the opposite direction!

[gwpercle]

I can tell you air cooled alloy's do harden with age .
The day after casting 9mm boolits with a 50-50 mix of COWW and soft lead .
dropping at .358" and sizing to .357" they sized very easy and my flat nose punch left a 1/8" dia. flat spot on the RN boolit .
Two weeks later they were noticeably harder to size and the nose punch left no flat spot on the RN boolit ... quite evident they had hardened over time ... I didn't think to test them ... I did but I don't have a tester .
Gary

[GregLaROCHE]

I haven’t tried the pencil method, but I’m not crazy about my Lee tester. Too hard to use and then I am not always confident I have a good reading. I’ve wanted to try pencils, but a variety of hardnesses is difficult to find over here.

[414gates]

I use the pencil on scrap to get a rough idea, then smelt all the scrap and confirm with the Lee tester.

[6622729]

I never became comfortable with the Lee tester. The pencils are way too easy. They're perfect for me. You file a flat on the end of the lead. Holding it at 45 degree angle to the lead, you are trying to gouge it. If it glides over the lead, the lead is harder. Go to the next harder pencil. File a flat on the tip and at a 45 degree angle, try again. Do this until a pencil scrapes up some lead. Your hardness is between those two pencils. Perfect!

[oley55]

I’d be afraid to speculate on the composition of fishing weights (or “sinkers”) since the exact composition is of virtually no interest to the folks who cast them. On “recovered” sinkers, I wouldn’t expect any two to be the same alloy, since they were probably lost by different fishermen.

Froggie

not sure what the composition of any few weights being different from others when a 100# has been bulk melted, stirred, fluxed and made into ingots. Feel pretty sure any one of those ingots is equal to it’s sister ingots. I suppose if you are melting and pouring sinkers directly into a bullet mold it would be a concern, but who does that?