The Old Argument: Actual Brinell Measurement/Hardness

[mehavey]

A couple of days ago -- on Another Forum Far, Far Away -- the usual "which hardness tester" debate started. Suggestions ranged from $6,000 Lab equipment down to simple ball / pressure impression diameter set-ups like LEE. The ubiquitous complaint of "I can't get the LEE microscope to work..." emerged as usual.

I suggested/showed a simple printer/scanner/PhotoShop solution for a 30-1 (RotoMetals) bullet that I'd just tested using the LEE steel ball indenter:

322969

That set off an absolute FIRESTORM in which I obviously could/wouldn't read the accepted science published/listed/specified everywhere that 30-1 is by definition BHN 9.
(Didn't I know the experts all said so?)


Well . . . No.
I have long used my own first principles calculation/test for Brinell, run against various alloys over the last 15 years.
It's fairly straightforward in both principle/test -- and calculation:

Very simple concept: Pressure (lb/sqin) which the material can withstand (i.e., quit) deforming
You press a small ball (LEE: 5/32") into the alloy at constant force (LEE: 60lbs) until the increase in depression surface area reduces the pressure (lbs per square inch -- remember?) to the point that deformation quits.

Final force on the spherical depression surface area of the material.
That's the Brinell #
322970

But . . . still the naysayers.

To the Cognoscenti here on CastBoolits then:
The Truth us out there.
What is it?

[waksupi]

If the Cabin Tree testers are still available, I found them to be the most consistent with the least fuss.

[Hick]

Well thought out-- never mind the firestorm. The thing that amazes me sometimes is how uptight people get about the bullet hardness. I have a bar of Lyman #2 I keep around for testing mystery alloy. I want my pistol bullets to be softer and my rifle bullets to be at least as hard. When I get my hands on mystery alloy I squeeze a ball bearing between the #2 and the mystery piece in my vice. I just compare the diameters of the indents-- the softer one will be larger-- to decide what to do with the alloy.

[mehavey]

Cabin Tree reference chart still has the Lead/Tin alloys w very high Brinell numbers.
Has anyone here done any actual/independent testing?

[charlie b]

Here ya go

http://www.lasc.us/Shay-BHN-Tester-Experiment.htm

[mehavey]

Here ya go
http://www.lasc.us/Shay-BHN-Tester-Experiment.htm

Those are all for very High/very Hard alloys (well above 20 BHN)
The question seems to be what's happening w/ the classic Low Tin/Lead ratios.
How soft are those.... ?

[Larry Gibson]

Here ya go

http://www.lasc.us/Shay-BHN-Tester-Experiment.htm

The important lesson from that extensive test and the tests conclusion; "So yes, these testers are a valuable asset to the bullet caster. Does my tester say an alloy is 18 BHN and the lab says no . . . its 20 BHN . . . Well, so what? It doesn’t matter as long as mine always says 17-18. Consistency matters, an exact match to lab results does not. If your casting technique is consistent enough to keep your bullets within 1 BHN and your BHN testing tool is consistent enough to measure within 1 BHN even the most demanding caster should be good to go. Alloy consistency is important for long range top end loads grouping and these tools are an important "aid" in assembling consistent cast bullet loads."

BTW; I've cast a lot of 30-1 alloy and never had a BHN of 9, regardless of what it says in the NRA Cast Bullet Handbook, using a Lee testor in a micro scope stand. I got consistent BHNs between 6 and 7.5 with multiple readings per sample. That's close enough for me as I know how much lead and tin were/are in the alloy. That BHN figure works for me.

[mehavey]

Just did a LEE retest from a 30:1 RotoMetals casting of 44-40s sitting from some 7 years ago:

323004

RotoMetals is nothing if not consistent. ;-)

[charlie b]

Those are all for very High/very Hard alloys (well above 20 BHN)
The question seems to be what's happening w/ the classic Low Tin/Lead ratios.
How soft are those.... ?

Like Larry said, that was only a comparison of the different testers.

I've never worried about it. The only thing I want soft lead for is my muzzleloader slugs and those can be in the 1-30 or so range. For my rifles I just buy Lyman #2. Pistols I don't care either. I ran straight COWW for decades and never measured bhn.

If you want to know for sure then send it to a certified lab who uses calibrated equipment, if you can find one.

[mehavey]

Charlie(b), I'm more interested to know why the accepted Lead/Tin alloys are
rated so high when really simple tests like LEE clearly indicate they are not.

Charlie(M) mentioned 20-1 being unequivocally 7.8 some time back, which is
consistent with my own 1st-principle Brinell definitions/processes.
https://castboolits.gunloads.com/showthread.php?165698-Lee-Hardness-Tester-re-calibration&p=1852750&viewfull=1#post1852750
Does anyone [ including Charlie(M ]8-)) recollect the source ?

More important (to me) than actual numbers when all dust settles, is why the absolutely
blatant discrepancy? w/ what should be such a simple alloy characteristic/measurement
method.

[charlie b]

Send some off to a lab and see who is right? Until then you have a comparison from your measurement device to base other measurements on.

[ioon44]

I have always used the LBT hardness tester it is close enough for my needs.

[mehavey]

I am less concerned the 'what,' so much as the WHY a direct Brinell tester
(Lee 5/32" ball impressed at 60-lbs pressure) provides exactly-correct
Brinell readings for certified pure lead (5), and certified Lyman#2 (15) ...

But (apparently ?) not for certified lead-tin alloys in between the two.

A spring constant is a spring constant is a spring constant . . .
Something is very wrong.

[DAVIDMAGNUM]

If the Cabin Tree testers are still available, I found them to be the most consistent with the least fuss.

https://cowboybullets.com/Lead-Tester_p_57.html

I have used one for years and have compared it to foundry certified samples from pure to Linotype. I have found it to be consistent. I truly don't care about the actual BHN, I just want to replicate a known alloy for my firearms and the purpose at hand.

side note: I don't need a tester to tell me that 30-1 bullets are soft. Accidentally dropping them on my concrete floor lets me know it......every time. :mad:

[fc60]

Greetings,

https://www.zwickroell.com/industries/metals/metals-standards/brinell-test-iso-6506/

"The test force is to be selected so that the average indentation diameter d is between 0.24 D and 0.6 D."

The Lee tester can only measure between 0.094" and 0.038" diameter of the test impression.

Cheers,

Dave

[mehavey]

THANK You for that article -- great info in practical Brinell applications.

That said, here are the indent range limits the article implies:
323060

The ARTICLE also mentions the indenter & forces associated w/ various Brinell#'s in Lead:
- BHN 5 - 25: Indenter of 5mm
- Force: 55 lbs

LEE's system has an indenter of 4 mm (5/32")
and uses a Force of: 60 lbs

All-in-All . . . a little over-force/under-indent, but a pretty fair match-up within Brinell# limitations

Lee reasonably ascribes to those limitations in their application chart:
323061

So 30-1 w/ an (assigned) BHN of "9" should be well within the LEE system -- no problemmo.


But problemmo it is.

So . . . .
- I've got a new (2nd) LEE tester coming in Tuesday
- I've contacted a local metallurgy lab

Film at Eleven . . . .

[MT Gianni]

Like it was said above, you want a repeatable alloy. If your alloy test to 6 bhn, and it shoots well it doesn't matter how it compares to another tester as long as you can make it again.

[mehavey]

you want a repeatable alloy. Not only consistent alloy, but consistent science.
(Otherwise we're just holding a wet finger in the air...
...and hoping.)
:holysheep ) :drinks:



* Notice I didn't say "settled" science :veryconfu

[Shopdog]

I'm interested in the $6k lab equipment. Have a name,or type?

We have 3 distinctly different pieces of kit here. 1st is a beam type torque wrench attached to an otherwise plain jane Lyman 450. It is EXTREMELY repeatable for plastic deformation.

#2 is a very nicely finished vertical impact tester. Designed after studying Charpy equipment.

#3 is a heavily beefed/scaled up,"accurized" cabine tree.

One not so minor detail on Lee testers,and not bashing them.... just sayin. They aren't direct reading. You're opening up,or encouraging "noise" by having to take a reading by interpretation of the input. Where as the cabine tree along with some others are direct reading. The Wilson style hardness testers are also direct reading.

[charlie b]

Interesting mix. When my father-in-law started casting he was intent on finding hardness as well. He had worked with Rockwell equipment (worked on explosives testing) so he built his own on a Lee turret press. He was also a machinist so he used the lathe and mill to make all the components necessary. His setup was within tolerance of the samples he tested at the lab. From his description the dia of the test ball was key to accuracy. He had two different ones for different alloys of lead.

[mehavey]

The ball diamter and the force used are the defining elements of the Brinell test.

Were the (current) LEE tester to not to dead nuts duplicate certified Lyman#2 as
BHN 15 (over many samples/over many years), I'd not be drundling around trying
to figure out why it's very consistently reading 5.7-6.0 for what is certified 30-1.
("supposedly" to BHN 9)

And were I not also able to read the sample indent diameters very precisely/repeatably
using both scanner and microscope (https://castboolits.gunloads.com/showthread.php?452304-45-acp-super-soft-bhn-experiment&p=5525893&viewfull=1#post5525893), I'd also not be scratching around trying for explanation.

But right now ... `tis a puzzlement.

[Shopdog]

Do you have a name or type of the $6k equipment piece?

[mehavey]

I'm going to a Lab (not buying the equip)

[Shopdog]

I misunderstood... reread the op and it still looks like someone suggested a $6k machine? The reason I asked was I'm looking for a used Wilson hardness tester and they're in the $1500 range. Grizzly sells a,and am assuming here.... a chyna copy. Would prefer the real McCoy.

[Larry Gibson]

Quite frankly, I find a +/- 0.5 BHN measurement to be quite acceptable when mixing up the same alloy. Based on taking 3 impressions per sample on many tests, I find trying to say a single 10.3 BHN measurement of an alloy indicates that sample is softer than a 10.5 measurement on another sample is futile.

[Shopdog]

Larry,just to blurt it out.... the only measurement I've found as an "absolute" is my torque wrench readings on slump,or plastic deformation. And this is only "practical" on longer rifle bullets where bending can be a major problem. Heck,I cast for 30 something years before getting a lead thermometer. And 5 of those was wearing out a Coleman stove. You know,just sayin.

[Shopdog]

But in these tool's defense ....

Our impact tester does show some very interesting results. Besides being highly repeatable.... and fun,smashing culls. So fully supportive of OP looking for a science lesson.

There's also some interesting things about penetration WRT tester contact point shape/size that whilst "may" not help in the search for truths in BHN,it can help understand some early upset on bullet points.

I know when machining custom TP's for an adj cup end set screw.... which depending on the screws set height,and torque to yield #'s... some dang interesting things can be seen on the nose forming. Mainly the swage propagation. Early on I'd have bet money on certain outcomes...only to lose that bet. Meaning what you think you know,ain't always what happens. The chemistry and dynamics may not add up... but it repeats,and repeats.

[mehavey]

I shipped a 30-1 sample off to AST (https://atslab.com/) this evening.
We'll see what comes back . . . .
:popcorn:

[Larry Gibson]

Larry,just to blurt it out.... the only measurement I've found as an "absolute" is my torque wrench readings on slump,or plastic deformation. And this is only "practical" on longer rifle bullets where bending can be a major problem. Heck,I cast for 30 something years before getting a lead thermometer. And 5 of those was wearing out a Coleman stove. You know,just sayin.

Yup, some parts of casting bullets and shooting them isn't rocket science. However, some parts are, just need to understand the difference......just sayin.

[M-Tecs]

I misunderstood... reread the op and it still looks like someone suggested a $6k machine? The reason I asked was I'm looking for a used Wilson hardness tester and they're in the $1500 range. Grizzly sells a,and am assuming here.... a chyna copy. Would prefer the real McCoy.

Watch Facebook Market Place and the local machine tool action sites. Ebay at $1.5K and shipping is far more than most non-machine shops are willing to pay.

I found a Wilson 3JR hardness tester for $300. It was hardly used 100% complete with extra penetrators and 8 certified test standard blocks. Listed weight is 325 pounds. I lifted it into the truck by myself. That's about the max I can do by myself.

Pics for reference here.
https://www.brystartools.com/wilson-rockwell-3jr-hardness-tester-refurbished/

[Shopdog]

Yup M-Tecs..... that would look SOOO nice sitting peacefully in our shop. Thanks.

[Digital Dan]

Have been using a Lee tester for a long time and find it perfectly useful. Whether or not it is spot on is irrelevant to me. What matters at the end of the day is how well the end product flies. I'm not a stranger to 5 shot one hole groups with various cartridges, but haven't a clue how to post pictures here.

One of the annoying aspects of the Lee tool is holding the magnifier steady. I constructed a small wooden holder for both metal sample and magnifier that works quite well. Not complicated at all.

FWIW, I don't have to use anything over 12 BHN for the .30-30 and max loads with a Lyman 311041. The levermatic shoots 5 in 1" at 50 yards. Once the alloy mix is determined it's simply a matter of mixing the recipe and casting while the Lee tool gathers dust.

[popper]

Nonsense.

[mehavey]

Nonsense.nonsense ?
In general... or in some specific aspect ?

[savage308]

nonsense ?
In general... or in some specific aspect ?

I have used the lee tester for many years and love it. I have a magnifying glass headband and use a regular digital caliper
And it works great for me

[MT Gianni]

Similar to lawn mowers, if you have only used a push hand mower it is the best there is. If you have $10K to spend you can't be satisfied with less than a zero turn.

[Larry Gibson]

I've found the Lee may not be the best there is nor the most expensive. However, using it in the toy microscope like I do I find it more than adequate.

323399

[Shopdog]

This cost me a little bit over half the price of the Lee. Think cabine tree on STEROIDS..

[KenH]

Shopdog, could you provide more info on that hardness tester? Looks interesting, but looks like it uses a spring for pressure rather than weights? I use the HR150A clone for hardness testing. It's normally used in the 60 Rc range with a diamond penetrator for knife blades. I made a penetrator using a 1/2" ball to test lead using the formula:
https://i.ibb.co/94N7dkk/Forumal.jpg

I use the 150kg weight to make the indentation, then measure the diameter of indentation with a stereo microscope at 20X to 40X power. I find the results usually agree pretty close with accepted numbers. I'm NOT saying they're "lab quality", but are repeatable for my use.

[Shopdog]

Just a beefed/accurized cabine tree.

It functions flawlessly but to be honest the vertical impact tester has much more potential. Mainly because it makes direct comparisons between the shape of the boolit,or bullet..or anything you want to test such as annealed cases. And there's also the torque wrenches that get used with Lyman 450's.

Not stating this as "fact"...or even a theory but; just a way I see the dynamics of launch and subsequent travel of the bullet. The impact tester is extremely important for launch,and there's more to it,becoming clearer the more I use it.... that alloy AND shape effects the launch,or how the bullet reacts to the initial "hit". Then once it's going,other factors come into play.

It reminds me of a race shock... they have generally two "circuits" that can be adjusted. A high speed shock like the edge of a pot hole(the launch or hit on a bullet)...

And a low speed circuit like going over a wave in the rd(this is a bullet's reaction to the lands going down the barrel). So while te BHN numbers are an insight.... it "may" not represent the challenges in of itself.

Throw in lube as part of the latter circuit. Yes there is some support on launch but not much compared to it's effect later in the cycle.

Edit to add annealing info...

[P Flados]

BHN is a direct measurement of the properties of the material.

I made my own tester and it functioned well enough. The principle is simple enough and the results are what they are.

Pure lead may be an exception, but in general I would be much less sure that any given "certified alloy" has a specific BHN. Material properties involve both the chemical composition and things like grain structure. Also "trace" amounts of materials other than the primary constituents can sometimes affect results.

So, be "happy" if you have gotten better at reducing uncertainties in your measurements. However, do not expect your measurements to tell you much more than the hardness.

[mehavey]

Of possible interest:
Test results back today of RotoMetals 30:1

AST (Applied Tech Services, Marietta, GA) BHN 5.8
This a $200 test and (for me 8-)) well worth it.
NOTE: Compare to LEE Tests/Post#1 (https://castboolits.gunloads.com/showthread.php?465089-The-Old-Argument-Actual-Brinell-Measurement-Hardness&p=5683410&viewfull=1#post5683410) and Post #8 (https://castboolits.gunloads.com/showthread.php?465089-The-Old-Argument-Actual-Brinell-Measurement-Hardness&p=5683640&viewfull=1#post5683640)


They're giving me another quote for an even more precise test,
which I might take them up on, just on general principles.
:drinks:

[dtknowles]

Of possible interest:
Test results back today of RotoMetals 30:1

323494
NOTE: Compare to LEE Test/Post#1 (https://castboolits.gunloads.com/showthread.php?465089-The-Old-Argument-Actual-Brinell-Measurement-Hardness&p=5683410&viewfull=1#post5683410)
This a $200 test and (for me 8-)) worth it.

They're giving me another quote for an even more precise test,
which I might take them up on, just on general principles.
:drinks:

Thank you sir.

Tim

[P Flados]

I remember trying to make a ~50# batch of medium hard alloy using starting out with near pure and adding in junk commercial hard cast, and some high tin stuff I had. I would add some hard stuff, poor an ingot and test it. Then add some more hard stuff. It remember that it took a lot more hard stuff to get above 6 than I expected. I was originally going for ~10, but stopped closer to 8.

I have seen what RotoMetals says for the BHN of the various lead - tin alloys they sell. Your test results are pretty far off compared to their number.

My guess it that either their info is just wrong, or it is based on some batches that had small amounts of "extra stuff" in them that pushed up the hardness.

[mehavey]

I have seen what RotoMetals says for the BHN of the various lead - tin alloys they sell.
Your test results are pretty far off compared to their number.

My guess it that either their info is just wrong, or it is based on some batches that had
small amounts of "extra stuff" in them that pushed up the hardness.
I started testing RM's 30-1 a decade ago, multiple batch orders over the years.
The results have never varied during all that time/all those batches: 5.7- 6.0

AST's lab test on the latest batch/sample verify those results: 5.8 in this case.
(BTW, no complaints at all. I deliberately cast & shoot for the hardness as it actually is.)

I believe what is happening is that "accepted BHN of 9" has been promulgated by
so many people, so many sources, so much internet lore that it has become
"accepted fact" -- notwithstanding no actual re-testing.

But I'm still going to have AST re-test with finer calibration standard.
We owe that to the everybody involved.
:drinks:


There's an old wry saying in physics:
When the data disagrees with the theory,
so much the worse for the data
:mrgreen:

[Recycled bullet]

Well thought out-- never mind the firestorm. The thing that amazes me sometimes is how uptight people get about the bullet hardness. I have a bar of Lyman #2 I keep around for testing mystery alloy. I want my pistol bullets to be softer and my rifle bullets to be at least as hard. When I get my hands on mystery alloy I squeeze a ball bearing between the #2 and the mystery piece in my vice. I just compare the diameters of the indents-- the softer one will be larger-- to decide what to do with the alloy.That's a really good idea

[KenH]

Of possible interest:
Test results back today of RotoMetals 30:1

AST (Applied Tech Services, Marietta, GA) BHN 5.8
This a $200 test and (for me 8-)) well worth it.
NOTE: Compare to LEE Tests/Post#1 (https://castboolits.gunloads.com/showthread.php?465089-The-Old-Argument-Actual-Brinell-Measurement-Hardness&p=5683410&viewfull=1#post5683410) and Post #8 (https://castboolits.gunloads.com/showthread.php?465089-The-Old-Argument-Actual-Brinell-Measurement-Hardness&p=5683640&viewfull=1#post5683640)


They're giving me another quote for an even more precise test,
which I might take them up on, just on general principles.
:drinks:

I think you've settle the value of 30-1 RM just fine. Thank you for spending the $200 for the test, not sure it's really worthwhile to spend even more money to confirm what you've already found out. I find it interesting that RM says "the Brinell Hardness Number of 1 to 30 Alloy is about 9.". Do they not test?

[Willie T]

I started testing RM's 30-1 a decade ago, multiple batch orders over the years.
The results have never varied during all that time/all those batches: 5.7- 6.0

AST's lab test on the latest batch/sample verify those results: 5.8 in this case.
(BTW, no complaints at all. I deliberately cast & shoot for the hardness as it actually is.)

I believe what is happening is that "accepted BHN of 9" has been promulgated by
so many people, so many sources, so much internet lore that it has become
"accepted fact" -- notwithstanding no actual re-testing.

But I'm still going to have AST re-test with finer calibration standard.
We owe that to the everybody involved.
:drinks:


There's an old wry saying in physics:
When the data disagrees with the theory,
so much the worse for the data
:mrgreen:

Out of curiosity did you have the content of the alloy tested? For me that would be the final piece of the puzzle. Was the alloy actually 30/1 lead/tin? I own the Lee tester. I never use the hardness tester. I make my own purpose specific alloys and have never purchased any ready made alloys. I’ve done a lot of experiments to determine what I can do with various alloys. I can easily repeat the alloys. Actual content of the alloy is what I’ve always been interested to know. I never paid much attention to bhn. That said, Lyman No2 is a good example of BHN driving the boat. Described as 90/5/5, Lyman gives recipes to alloy No2 with either clip on wheel weights or Linotype as the base of the alloy. The recipes approximate the same hardness but their composition is quite different. Before someone gets wrapped around the axle about it having to be 90/5/5, it is Lyman’s alloy and Lyman’s recipes. Obviously Lyman No2 is about how to generate an easy casting alloy of a given BHN, rather than content.

[mehavey]

I have been purchasing certified alloys from Rotometals since 2012.
They have been absolutely consistent in both service and product.

So too have their alloys (90/5/5 Lyman #2, and 30-1) "Lee" tested as well:
#2 at Brinell 14.9-15.0; and 5.7-6.0 for 30-1.

Today ATS/Marietta came back w/ the extended ASTM E10-23 test on the 30-1 Alloy Ingot:
5.88 HBW(tungsten) indenter

[Willie T]

I have been purchasing certified alloys from Rotometals since 2012.
They have been absolutely consistent in both service and product.

So too have their alloys (90/5/5 Lyman #2, and 30-1) "Lee" tested as well:
#2 at Brinell 14.9-15.0; and 5.7-6.0 for 30-1.

Today ATS/Marietta came back w/ the extended ASTM E10-23 test on the 30-1 Alloy Ingot:
5.88 HBW(tungsten) indenter

Have you had the alloys tested for content? What you had tested consistently came back with pretty close numbers for hardness. Have you verified that it is in fact 96.8% lead and 3.2% tin? Testing the same batch of alloy you had tested for bhn for content would lend credence to your assertion of the true hardness of 30:1.

[mehavey]

I have no (zero) doubt that RotoMetals is producing/selling accurate/virgin alloys.

But if you really doubt that . . . .

[Willie T]

I have no (zero) doubt that RotoMetals is producing/selling accurate/virgin alloys.

But if you really doubt that . . . .

I’m not the one making the big deal about testing methods. I’m not trying to besmirch RotoMetals either. I have never bought casting alloys from them. I mix my own. I have had some of my own alloys tested for content, even though I completely trust myself. I am well versed in generating data through R&D. The first rule in testing something is to verify what you are testing if you want to compile reliable data points. Maybe I didn’t follow what you were trying to establish by having your alloy independently tested for hardness twice. Were you doubting Lee’s claims about their hardness tester or trying to determine the actual bhn of 30:1?
Willie

[dtknowles]

I’m not the one making the big deal about testing methods. I’m not trying to besmirch RotoMetals either. I have never bought casting alloys from them. I mix my own. I have had some of my own alloys tested for content, even though I completely trust myself. I am well versed in generating data through R&D. The first rule in testing something is to verify what you are testing if you want to compile reliable data points. Maybe I didn’t follow what you were trying to establish by having your alloy independently tested for hardness twice. Were you doubting Lee’s claims about their hardness tester or trying to determine the actual bhn of 30:1?
Willie

I think the issue is that common knowledge has 30:1 being considered harder than it actually is, should be 6 BHN but often thought to be closer to 9 BHN. In a way the hardness does not matter, if the application calls for 30:1 just make or buy 30:1 and don't worry about the hardness. I think me and my Lee tester are close enough, but hardness will not tell you actual composition. I use a lot of range scrap and wheel weights so while I can test for hardness, I don't know actual composition. I don't use 30:1 for anything so I don't have a dog in this fight but if I have an alloy with a BHN of 16 is it 2% tin and 6% antimony or is it 5% tin and 5% antimony. This can become important if you want to formulate a softer alloy using this alloy as a component. One you mix it 50/50 with pure you get 1% tin and 3 percent antimony and the other you get 2.5% tin and 2.5% antimony. The later will probably be easier to cast good bullets and will be just as hard and more ductile.

Tim

[mehavey]

If the Gentle Reader wants to see the origin of this discussion, see these posts in order:

https://www.marlinowners.com/threads/brinell-hardness-tester.662906/post-8839428
https://www.marlinowners.com/threads/brinell-hardness-tester.662906/post-8839437
https://www.marlinowners.com/threads/brinell-hardness-tester.662906/post-8839472

(I think it was the opening line of the 3rd post
"...Sounds like someone knows more than the industry engineers that set the standards.
Maybe all my college engineering professors did not know what they were teaching was wrong..."
...that lit the fire.[smilie=l:

But in reality, knowing the actual hardness of common lead-tin alloys -- which are unique in being almost immediately age-stable -- is of no small importance... especially if the "accepted internet lore" has them as much or more than 50% harder than they actually are.
:coffeecom

Naturally, powder-coating has largely thrown all that out the window lately by making even the softest bullets effectively "polyester/epoxy-patched," and able to be pushed really hard.
https://castboolits.gunloads.com/showthread.php?457804-Shake-amp-Bake&p=5592837&viewfull=1#post5592837
https://castboolits.gunloads.com/showthread.php?409893-Pure-Lead-amp-PC&p=5001471&viewfull=1#post5001471

... but there's always those pesky bore riders that don't like the extra PC girth along those long noses.
:evil:

[charlie b]

... but there's always those pesky bore riders that don't like the extra PC girth along those long noses.
:evil:

But for those of us who use them with PC there are nicely made nose size bushings from NOE :)

[mehavey]

I'm going have to probably break down and look at those nose bushings.... [smilie=f:

[tnflyfisher]

I have the Lee hardness tester and Veral Smith's which I like a lot better. Smith's is quick and easy to get repeated results. I have trouble getting a consistent read from the Lee scope. Smith still has a few testers available at lbtmolds.com although he is out of business for molds. His shop completely burned down last Christmas eve. Sorry to see all that end, I like his molds and products.

[mehavey]

I have trouble getting a consistent read from the Lee scope.
Forget the Scope (for now).
Just put it on your printer/scanner at 9600 px/in and reading the indent diameter becomes a no-brainer.

325278
(Certified RotoMetals 30-1)
;-)

[Chill Wills]

mehavey
Question....
With your system, does Roto Metals 30-1 read as a BHN of 5.7????

[mehavey]

5.7 - 5.9 BHN (Rotometals * )
Not only the Lee tester/scanner reading the impression -- same readings over multiple samples, multiple years, three different testers. **
....but the Materials Testing Lab I sent the 30-1 ingot to so as to settle the debate back 5-6 weeks ago.

Applied Technical Services (https://atslab.com/locations/marietta-ga/), Marietta GA ***
IAW ASTM E1479-16, ASTM E1621-22, and ASTM E10-23

--- Pb - Sn - Si
% 96.4 3.6 0.1 (* effectively 29.9-to-1.1)
Test 1: BHN 5.8 1st Test w/ Basic reference
Test 2: BHN 5.88 2nd test w/ Precision reference

There's never really been any issue in my mind as to actual hardness of the classic 30-1 alloy, and good use of it over those years.
Perfectly good performance (and great expansion as you might expect) in moderate/traditional load ranges.
I've loaded it for what it was in actuality.

** Tidbit from several years ago:
https://castboolits.gunloads.com/showthread.php?165698-Lee-Hardness-Tester-re-calibration&p=1852750&viewfull=1#post1852750]

*** Good people. I recommend them,

[Chill Wills]

If that is the case, there are a lot of really bad charts and info floating around for a century or more.
Interesting!!!

Just for grins, what does pure Pb come in at?
Silicon, Si is listed in one alloy in your post, (0.1%) Pb-Sn-Si. You don't normally see that other than background contaminant.

[mehavey]

I see the (less-than-1/10th-of 1%) silicon to be residual from the gross ore smelting process.

Pure lead (RotoMetal) comes out at 4.5-4.6 BHN.
Reactor Grade lead just a decimal point lower

[fc60]

Greetings,

We had a batch of metal X-Ray analyzed at the local scrap yard.

Came back with a high Silicon content, about 2%.

Next visit, we asked the yard man to clean the lens of the analyzer.

Testing the same ingots, the Silicon value disappeared!

Cheers,

Dave

[mehavey]

--- :killingpc ---
---:drinks:---

[Chill Wills]

I see the (less-than-1/10th-of 1%) silicon to be residual from the gross ore smelting process.

Pure lead (RotoMetal) comes out at 4.5-4.6 BHN.
Reactor Grade lead just a decimal point lower

Thanks for getting back to me. The BHN for Pure Pb is on track with many sources. At least that hasn't changed. :p

BHN has been a keyboard conversation for the 25 years I have been following it. Especially in the BPCR world.

I am very open mined. Without jumping in with both feet, one thing I think I know is the BHN of any alloy is not fixed, but Dynamic. There are so many external conditions that can and will effect it.

Thanks for any time and work you have done.

[mehavey]

Binary Lead/Tin alloys aren't affected by either quenching or aging.
They are effectively what they are, near immediately, and stay that way.

Ditto actual Lyman#2 at 90/5/5 Lead/Tin/Antimony.
I've tested 30 minutes after -- and three years after -- still BHN 15.
(I'll have to go re-heat/fast-quench a couple of bullets again and re-check there)

Add any arsenic... divert from equal parts tin/antimony... and you're in another ball game. 8-)

[mehavey]

See above belief that (true 90/5/5) Lyman #2 is not affected by quenching.
...and that I would re-check.

I recast both air cooled and fast-quench (direct from hot mold into ice water) RotoMetals actual Lyman#2 last night.

Air-cooled was BHN 14.9 from 30 minutes on to current 24 hours later -- no change
Fast quench went from BHN16.6 one hour after; 18.6 four hours later; and now 21.2 twenty-four hours later.

I stand self-corrected. [smilie=p:


325439

[Chill Wills]

Binary Lead/Tin alloys aren't affected by either quenching or aging.
They are effectively what they are, near immediately, and stay that way.


This is been in interest of mine for decades. This is what I think I know about Pb - Sn alloys and time.
Look to the bottom sited quote below.

I have other data including samples I have tested on my own. This isn't a hill to die on for me. Just interesting.
++++++++++++++++++++++++++++++++++++
Totalmateria

Materials science database

Heat Treating of Lead and Lead Alloys

Abstract:
Lead is normally considered to be unresponsive to heat treatment. Yet, some means of strengthening lead and lead alloys may be required for certain applications. Lead alloys for battery components, for example, can benefit from improved creep resistance in order to retain dimensional tolerances for the full service life. Battery grids also require improved hardness to withstand industrial handling.
Solution Treating and Aging

Adding sufficient quantities of antimony to produce hypoeutectic lead-antimony alloys can attain useful strengthening of lead. Small amounts of arsenic have particularly strong effects on the age-hardening response of such alloys, and solution treating and rapid quenching prior to aging enhance these effects.

Hardness Stability. For most of the two-year period, the solution-treated specimens were harder than the quench-east specimens. Other investigations have also shown that alloys cooled slowly after casting are always softer than quenched alloys. The alloys with 2 and 4% Sb harden comparatively slowly, and the alloy containing 6% Sb appears to undergo optimum hardening.
A useful level of strengthening normally requires solute additions in excess of the room-temperature solubility limit. In most lead alloys, homogenization and rapid cooling result in a breakdown of the supersaturated solution during storage. Although this breakdown produces coarse structures in certain alloys (lead-tin alloys, for example), it produces fine structures in others (such as lead-antimony alloys).

In alloys of the lead-tin system, the initial hardening produced by alloying is quickly followed by softening as the coarse structure is formed.