Cabin Tree Hardness tester Reference Chart

[54bore]

I bought a new Cabin Tree Hardness tester from Buffalo arms, this one is made by ST Machining, stil in Dayton Wa, but has changed ownership. Anyone else notice the Discrepancies in the reference chart? I believe the new chart that comes with these units from ST Machining is WRONG? I did several tests on known pure plumbers lead and got a dial reading of .025-.026, the reference chart that came with my Cabin Tree doesn't even go that low, I understand that one should know that is pure lead, just a fact that the Old Reference sheet DOES go that low. Also according to my chart my bullets are 8BHN (this is a big deal to me!) According to the old original chart my bullets would be 9-9.5BHN, Again I believe the old original chart to be correct and the New one that comes with testers now I believe is incorrect? Idahoron and i are gonna run some side by side tests in a couple of months of same lead and see if our dials read the same? Anyone agree, disagree here?

This is the chart that comes with the New Cabin Trees, from ST Machining
Attachment 193310

This is the old Original reference sheet that came with the units years ago.
Attachment 193312

[Crusty Deary Ol'Coot]

54Bore,

Will be interesting to follow this thread. I have a "used" Cabin Tree tester I bought from an internet friend from Ohio. Mine also came with the older info.

Crusty Deary Ol'Coot

[mold maker]

My 6yo unit also has the older list. It is possible that the new producer may have found it expedient to make small un-noticed production changes, that necessitate a change to the paperwork. Neither list, nor that of any other tool, can be held as gospel. They are relative only as reference #s for that particular tool. Since the CabineTree is hand produced, there will naturally be small discrepancies from one tool to the next.
Since all brands require mathematical translations to get to BHN, and each is a different formula, the end results will differ slightly.
Don't get all bent out of shape over BHN in our hobby. It really has little to do with exact numbers, but instead, relative ranges.

[OS OK]

This BHN business isn't an exact science with any of these testing tools we use and those expensive testers are not what you might think...read the results of this extensive testing and you might have a change of heart...

Cast Bullet BHN Tester Experiment

***A synopsis of the testing...

Initial Analysis of Results:

Top of page

• At initial glance, LBT and SAECO tools seem to have the highest standard deviation. Throwing out the high LBT tool reading and eliminating the early test that was redone with a different batch of bullets closer to the testing date moves the standard deviation more into line with the Cabine Tree and Lee testers.
• Cabine Tree, LBT, and Lee tools appear to have been equally consistent within their groups for this particular batch of bullets. SAECO seemed to have more variance, due in part to conversion factors.
• SAECO and Cabine Tree BHN estimates were more dependent on user conversion from the raw data reading into a BHN number than the LBT and Lee tools.
• The Cabine Tree numbers could be more accurate with more “mapping” of the correlation between indent depth and actual lead hardness.
• LBT numbers were closest to the actual lab results, with all other tools measuring the samples as harder than reported by the laboratory. This is especially true if the “high tester” set and the early duplicate test are eliminated from the data. SAECO and Cabine Tree testers measured the farthest from the actual lead hardness.
• Cabine Tree tools produced the smallest extreme spread, while the LBT tools produced the largest. If the LBT high test is removed, then the SAECO would appear to have the highest extreme spread.
• The Lee tester appeared to produce the most readings that were both consistent and closest to the actual laboratory results. Although individually other testers came in with slightly smaller standard deviations and numbers that came in closer to calibrated equipment, the Lee appeared to have the best combination between the two areas.
• The differences in the SAECO numbers raised the question of if there was any correlation between the age of the tester and the BHN that was reported. A query was sent out to the SAECO users to determine if their tools were the older, metallic colored ones, or the newer, yellow anodized aluminum ones. Testers 5, 9, 12, 16, and 17 were reported to be the newer yellow testers. Testers 15, 26, and 44 were older, metal colored units. This information seems to indicate there is not a correlation between the jump in numbers on the SAECO'S and age of the tools. There has been no response from tester 37 yet, but at this point it is doubted the age of the tester (equipment) will shed much more light on any age to measurement connection than the initial responses already have.
• An experience that may be relevant to this experiment was reported by user Dye (with SAECO testers 16 and 17). He sent his testers back to the company when the measurements of one of his alloys did not come back the same between the two testers. When they were returned to him they still provided different readings. Although the deviance did not appear to be present for this particular alloy (in this test), Dye's experience may or may not shed light on other differences that have appeared between SAECO'S in this test. There simply isn't currently enough information collected to determine the cause of the differences beyond the shadow of a doubt. It could be simply that this alloy was harder than the "sweet spot" that this particular brand of tester measures accurately.

[lightman]

When you get familiar with a certain tool it can give you an idea of what you have. Its not exact and it won't tell you the exact alloy. Will be interested it the comparison between the two tools.

[54bore]

Here is a response i got from the Cabin Tree website, this guy sold part of his business to an outfit called ST Machining, the Testers being in the sold part. I have emailed ST Machining as well but they have not responded yet

I no longer make the testers. I sold the company 3 years ago. The
current company is at cowboybullets.com

If the old chart works for you, I would suggest using it. It is still
on my old web site, castingstuff.com and you can print as many
copies as you need.
Jim