Lead Hardness Testing Method/Updated with pellets tested



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Re: Lead Hardness Testing Method
« Reply #20 on: November 08, 2018, 07:17:41 PM »
the only way to properly determine hardness was to find both the tester which does, and does not, scratch the sample....

Makes perfect sense to bracket a binary characteristic.  Else, one is left guessing "how much" harder or softer.
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Offline Nvreloader

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Re: Lead Hardness Testing Method
« Reply #21 on: November 08, 2018, 09:18:20 PM »
Bob

I never thought along those lines, I guess I'll get the 7B & 8B pencils for the set also,
just make sure, as I don't need the harder end.   ;)

I am very curious as to the hardness of the pellets I have, 17 thru 25 calibers.
I know there is a difference between the older and newer Crosman pellet I have in stock.

I just got thru testing some pure sheet lead, that I melted down in a new clean pot,
and found the 6B pencil cuts a trough, very easily etc.

Thanks,
Don
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Re: Lead Hardness Testing Method
« Reply #22 on: November 08, 2018, 09:42:24 PM »
Quote
the 6B pencil cuts a trough, very easily

Exactly why I want to try 7B and 8B.... It may well be that we can differentiate between pure lead and 1% tin by doing that....

Bob
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Re: Lead Hardness Testing Method
« Reply #23 on: November 09, 2018, 12:00:02 AM »
Bob

First off, let me apologize to you, for the comment on my post #17,
I was not attempting to be a smart Azz,
I thought that maybe you knew something, that I had no info about............ :-[

Do you think that when using these pencils, (I don't know the answer),
that they could find that small a percentage of of tin or any harder material in lead, or OEM pellets out there?

I just ordered a 7B & 8B pencils to add to my set, waiting for them to get here,
I could not find any in the 9B range, but I found out the hardness can go up to 9H.  :o

Thanks,
Don
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"We must reject the idea that every time a law's broken, society is guilty rather than the lawbreaker,
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Offline rsterne

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Re: Lead Hardness Testing Method
« Reply #24 on: November 09, 2018, 01:36:12 AM »
I saw a reference for a 7B being pure and sheet lead, and a 6B for lead wire, while a 5B is for 40:1 (2.5% tin). I was hoping that with experience we might be able to differentiate 1% tin from the others, but only experimenting will tell us for sure....

Bob
  • Coalmont, BC, Canada
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), .22 QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Bench PCP, 6mm Regulated PCP and .257 Unregulated, Three BRods.

Offline Nvreloader

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Re: Lead Hardness Testing Method
« Reply #25 on: November 09, 2018, 12:34:46 PM »
Thanks Bob

The pure lead, I tested was from a section of cable sheathing/piping, approx 6" in dia,
which was melted down, then tested etc.

Tia,
Don
  • Western  NV
Hammerli 850 Air Mag -17 cal x 2, 22 cal
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"We must reject the idea that every time a law's broken, society is guilty rather than the lawbreaker,
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Online Gut2Fish

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Re: Lead Hardness Testing Method
« Reply #26 on: November 12, 2018, 06:41:24 AM »
NVReloader, your post on scratching a pellet stated a 3B was 25:1 alloy but my chart says 20:1 is 3B. The first pencil to scratch it is of equal hardness to lead so by my chart your pellet is 10 BHN.

I'll have to check my set of pencils. Find them first is more like it. Don't remember if my set went softer than 6B or not. My "pure" lead is 99.8% and 6B scratches it. 99.99% pure lead is available and it's quite possible a 7B will scratch it.

Keep in mind "pure" lead is a relative term. Natural impurities are present unless cleaned away. This is why BHN of lead is listed as 5 but if you use ultra pure lead it is actually lower than 4.5 BHN. Bob uses the purest Rotometals so there is a very good chance the 7B will scratch pure and 6B scratch 1% tin. Using his Rotometals that 1% is really a touch over 5 BHN, far softer than 6BHN.

I'll rummage around this morning before work, locate pencils and if I have a 7B will check my 99.8 lead to report back.

« Last Edit: November 12, 2018, 06:50:10 AM by Gut2Fish »
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Re: Lead Hardness Testing Method
« Reply #27 on: November 12, 2018, 07:33:44 AM »
As suspected, my cheapo set doesn't have a 7B but has an 8B and jumps to 6B.

6b scratches my "pure lead", 8B not even close. My hand mix of 1% tin alloy requires 5B to scratch it. I've a cheap set who's ASTM hardness standards are not as exacting as a quality Steadler set and also have not so pure "pure" lead as base- 99.8%.

Something to keep in mind is alloy require curing time. Tin alloy will soften with age and antimony alloy hardens with age. Like all cures, full time is 21 days but 85%  of curing is in after 7 days.
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Offline Nvreloader

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Re: Lead Hardness Testing Method
« Reply #28 on: November 12, 2018, 01:24:35 PM »
Garrett

Thanks for your info, and finding the mistake I made,
I see, that I miss quoted the wrong range, that what I get for flipping from one site to another,   :-[
I have correct this mistake on my post.

Question for you,
Which chart are you using? Do you have a different chart?

The chart I was referring to was, this one: (was posted on the cast bullet forum),
https://i.imgur.com/frAfUvB.jpg

I can't seem to copy and paste this chart etc, to keep the same info thru all the posts and have the correct info etc.

I have the 7 & 8B pencils coming, and I am attempting to find a 9B pencil to add this set also.
Once I have all these pencils, then I'll do my test on all the pellets I have and post the results etc.

I am aware of the curing times of alloys, I have some lead that was cast from the late 70's,
and will be testing them also, I do remember that they were HARD, with Lino added, for a 357 Mag project etc.

I for one, would be greatly interested in any and all info, related to this type of testing etc.

Thank you,
Don
  • Western  NV
Hammerli 850 Air Mag -17 cal x 2, 22 cal
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Re: Lead Hardness Testing Method
« Reply #29 on: November 12, 2018, 01:47:28 PM »
I think it's the same chart just in a different location and format- jpg file.

http://preppersvoice.com/wp-content/uploads/2016/06/Pencil-hardness-test-versus-Brinell-hardness-of-lead-alloys.jpg

I don't see a need for 8 or 9B pencils. You're not going to get softer than 7B lead and that's even if the ultra pure 99.99% lead is able to be scratched by a 7B. Good chance it can as it's definitely closer to 4 BHN than it is to 5. Lead with impurities like mine, 99.8%, and sheet lead are at 5 BHN.

Each % of tin raises the BHN by 1. We just always assume the base lead is 5 but if a person is starting with pure lead then 4-4.5 is the real number. So a 40:1 would be 6.5 - 7 BHN, 25:1 would be 8- 8.5 BHN and so on. The constant is adding a percent per percent tin. The variable is how pure your base lead is.
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Re: Lead Hardness Testing Method
« Reply #30 on: November 12, 2018, 02:23:28 PM »
Rotometals state that their 40:1 alloy (2.5% tin) is BHN 8.... but I have never checked it....

Bob
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Re: Lead Hardness Testing Method
« Reply #31 on: November 12, 2018, 03:14:17 PM »
Thanks Guys

Garrett
That chart is the same one I am using.

I don't have enough info to figure out the % if tin to lead ratio yet and see if the info follows thru with the pencil testing etc.

If I have the complete range of pencils, then I can say which ever pencil range cuts the lead,
and the next softer range does not cut the lead etc, then the BHN should be around this range.

If the same chart is used by all, then the info given or posted should be relatively close,
the only item that would change these ratings, would be to have the lead tested for the exact % of mixtures,
and then the pencil test would be fairly close etc. IMHO

I am hopeful that enough info will come forth to have good usable info, for everyone to follow etc.

Tia,
Don
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Online Gut2Fish

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Re: Lead Hardness Testing Method
« Reply #32 on: November 12, 2018, 06:33:38 PM »
Rotometals state that their 40:1 alloy (2.5% tin) is BHN 8.... but I have never checked it....

Bob

Bob,

I doubt RotoMetals performs hardness tests. My thought is they are posting what's convention. I would bet doughnuts if one mixed an alloy 40:1 with their 99.9% and tin they'd be at 7 BHN. Not that it really matters in the grand scheme of things.

The only part it matters is if a 7B can cut their pure lead. Then you'd never mix up the pure and 1% ingots again. LOL. Seriously, pencils are awesome and darn accurate. I love em. As stated before it's saved me from casting with 10 BHN lead that was left in the pot before and of if I don't label piles of ingots it reminds me which pile was 2% and so on.
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Re: Lead Hardness Testing Method
« Reply #33 on: November 12, 2018, 08:32:14 PM »
I did find this info while on the Roto-Metal site,

I did find out the BHN of their pure lead, The Brinell Hardness scale of 99.9% Lead,
Brinell hardness is approximately 5.

Basic Rules for Hardening Lead-
For every 1% additional tin, Brinell hardness increases 0.3.
For every 1% additional antimony, Brinell hardness increases 0.9.

Their Pure Lead percentage,
ELEMENTS
Lead (Pb) 99.9241
Tin (Sn) <0.0001
Antimony (Sb) 0.0237
Copper (Cu) 0.0232
Arsenic (As) 0.0002
Bismuth (Bi) 0.0232
Silver (Ag) 0.0027
Nickel (Ni) 0.0004
Zinc (Zn) 0.0001
Iron (Fe) <0.0001
Cadmium (Cd) <0.0001
Other Sb+Sn+As 0.0239

For a simple equation,
Brinell = 8.60 (Antimonial Lead) + ( 0.29 * Tin ) + ( 0.92 * Antimony )
Antimonal lead = This alloy consists of 95-97% lead and 3-5% antimony.

1 to 40 lead alloy
This alloy is comprised of forty parts of lead and one part of tin (97.5% lead, 2.5% tin),
and consistently expands at black powder velocities with excellent weight retention.
The Brinell Hardness scale of 40 to 1 alloy is approximately 8.5.

1 to 30 lead alloy
This alloy is thirty parts of lead and one part of tin (97% lead, 3% tin).
The Brinell Hardness Number of 1 to 30 Alloy is about 9.

1 to 25 lead alloy
This alloy is comprised of twenty five parts of lead and one part of tin(96% lead, 4% tin).
The Brinell Hardness Number of 1 to 25 Alloy is approximately 9.

1 to 20 lead alloy
This alloy is comprised of twenty parts of lead and one part of tin (95% lead, 5% tin).
The Brinell Hardness Number of 1 to 20 Alloy is approximately 10.

1 to 16 lead alloy
This alloy is 16 parts of lead and one part of tin (94% lead, 6% tin).
The Brinell Hardness scale of 16 to 1 is approximately 11.

Our Lyman #2 alloy (90% Lead, 5% Tin, 5% Antimony).
The Brinell Hardness of this Lyman 2 alloy is about ~ 16.

Metals Analysis Test XRF
***This for the test only, we do not sell Scientific Analyzers***
We can test your metal samples, items, toys etc. to tell you what alloy you have or what metals are present in your paint or plastic.
We also can see then if we can match that and create more of that alloy for you.
We can check for the following elements: Tin (SN), Antimony (SB), Copper (CU), Bismuth (BI), Silver (AG), Iron (FE), Nickel (NI),
Zinc (ZN), Cadmium (CD), Lead (PB). Indium (IN).

We use a New Thermo Scientific Niton XL3t XRF Analyzer.

HTH,

Tia,
Don
  • Western  NV
Hammerli 850 Air Mag -17 cal x 2, 22 cal
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Offline rsterne

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Re: Lead Hardness Testing Method
« Reply #34 on: November 13, 2018, 12:12:54 AM »
I was at a Staples today, and they had the Staedler pencil sets on sale.... I picked up the 100G12S set, which covers 2H to 8B.... I plan to use the standard Staedler Mars Lumograph 23 deg. sharpener for consistency, and will push the point of the pencil away from me while holding the pencil at about 45 deg. to the surface of the lead.... At least that is the plan, I may have to use a steeper angle, say 60 deg.... whatever works so that the force is roughly in line with the pencil, and not trying to break the lead....

I have been thinking about the method of exposing a parallel section of lead and sanding it square.... or sharpening it to a chisel edge.... and I think you may not be measuring the hardness of the lead with that method, but rather the shear strength of it.... If you look at the photos where they are using that method, they are looking for a "curl" of lead forming ahead of the pencil, much like the way a chip curls from a drill bit, or lathe tool.... The ease of cutting is greatly dependent on the angles of the tool, and the angle it is held to the work, for you are actually shearing off a sliver of lead, not just doing a "scratch" test.... For this reason I think using a consistently sharpened pencil, pushed away at the correct angle, and looking for a simple scratch (eg. a shallow channel) may be a better indicator of hardness....

I think either method can work.... but I'm not sure that they are actually measuring the same thing, ie the hardness, which is what we want.... I haven't tried this yet, but I think there is a difference in the two methods, and the results they will give.... I guess I'll find out !!!

Bob
  • Coalmont, BC, Canada
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), .22 QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Bench PCP, 6mm Regulated PCP and .257 Unregulated, Three BRods.

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Re: Lead Hardness Testing Method
« Reply #35 on: November 13, 2018, 02:52:24 AM »
I'm going to stick with pure lead from Rotometals myself, I'm having really good luck with it using it on my .22's and .25's ;D
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Re: Lead Hardness Testing Method
« Reply #36 on: November 13, 2018, 03:26:21 AM »
Thanks Bob

I modded a sharpener the way it was posted by Grmps,

I found that the sharp edge of the lead flattened to a full dia of the pencil lead,
will bite into the lead and cannot be moved forward on or about the 45* angle, without breaking the lead,
I tried pushing on the very end of the pencil and holding the pencil at the 45* angle etc.

When I changed the angle of attack to around 15-20*,
the pencil could be pushed forward and the pencil lead would cut a trough into the lead, that could be felt,
with the curl of lead, left at the end of the trough, from the pencil lead etc.

I then used an adjusted angle finder to get a workable angle, with better results and I could keep the correct angle,
every time for pushing the pencil forward with good results.

A softer pencil would just slide forward, leaving a pencil lead smear and NOT cut a trough or dig in,
going the next harder pencil would push up a curl of lead.

Once we come up with an approximate angle that works and gives good results,
I plan making a alum angle gage, so I am using a somewhat standardized angle for good results etc.

I'll be waiting for your info on what you find as to the angle etc, I tried using the 45* angle of a square,
and found out about the steepness 45* did not work for me, as I posted above. (I may have not been doing it right).

Tia,
Don
  • Western  NV
Hammerli 850 Air Mag -17 cal x 2, 22 cal
QB-79 - 22 cal
AF Recon Condor 22 cal- pending
CF 4500 45 min SCBA tanks x 3, w/SB F-10 compressor

"We must reject the idea that every time a law's broken, society is guilty rather than the lawbreaker,
It is time to restore the American precept, that each individual is accountable for their actions."
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Re: Lead Hardness Testing Method
« Reply #37 on: November 13, 2018, 03:41:56 AM »
Thanks Wayne

From the photo's you have post, those pellets look and have better results than OEM pellets,
I hope, I can have the same results, when I start casting them.

I would like to buy 15-25, 22 cal pellets, that you have cast from the Roto-Metal pure lead,
this would be used as a standard of the hardness to go by.

I'll send you a container to ship them in, to reduce any damage etc, if you want to send them etc.  ;)
Just drop me a PM with the info needed to send the item to you, and the funds will be included,
for return shipment/payment.

Tia,
Don
  • Western  NV
Hammerli 850 Air Mag -17 cal x 2, 22 cal
QB-79 - 22 cal
AF Recon Condor 22 cal- pending
CF 4500 45 min SCBA tanks x 3, w/SB F-10 compressor

"We must reject the idea that every time a law's broken, society is guilty rather than the lawbreaker,
It is time to restore the American precept, that each individual is accountable for their actions."
Ronald Reagan
-----------------------------------------------------
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Offline rsterne

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Re: Lead Hardness Testing Method
« Reply #38 on: November 13, 2018, 12:46:59 PM »
I can believe that you would need a very shallow angle if you square off the end of the lead.... It is working like a lathe cutting tool, or a chisel in creating the curl.... My concern is that you are actually measuring the shear strength of the lead, and not the hardness, but I could be in error....

Scratch tests in rockhounding are done using point or corner to see if it leaves a "scratch" mark....

Bob
  • Coalmont, BC, Canada
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), .22 QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Bench PCP, 6mm Regulated PCP and .257 Unregulated, Three BRods.

Offline rsterne

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Re: Lead Hardness Testing Method
« Reply #39 on: November 13, 2018, 04:02:43 PM »
My preliminary testing show the following....

On a Rotometals pure lead ingot with a freshly cleaned surface (sanded smooth)

8B crumbles
7B leaves a shallow scratch
6B leaves a deep scratch

On a bullet cast with Rotometals pure lead with 1% tin added

7B barely leaves a mark while crumbling
6B leaves a decent scratch
5B leaves a deep scratch

On a Rotometals 40:1 (2.5% tin) ingot with a freshly cleaned surface (sanded smooth)

6B crumbles
5B leaves a decent scratch
4B leaves a deep scratch

On Rotometals "popcorn tin", remelted on wood, and then the underneath surface (was against the wood) sanded smooth....

4B crumbles
3B barely leaves a mark while crumbling
2B leaves a shallow scratch
B leaves a deep scratch

Using the previous "pencil scratch" tables, I would conclude that very pure lead is about BHN 4, 1% tin is about BHN 6, 2.5% tin is about BHN 8, and the tin I had is about BHN 11 (very pure tin might be slightly softer).

Incidently, I tried scratching a JSB King pellet, and the 7B pencil left a decent scratch, so I would conclude that pellet is pure lead.... Another note, "my" fingernails easily scratched the 40:1 alloy, but would not scratch the tin, although they left a mark not unlike the 3B pencil.... I would conclude that the fingernail test, for me, can differentiate alloys softer than BHN 9, which means they are probably good enough for airgun use.... If I can scratch it with my fingernail it is probably OK for airgun use, if I can't, it's too hard.... YFMV (your fingernails may vary).  ;D

Bob
« Last Edit: November 13, 2018, 05:56:16 PM by rsterne »
  • Coalmont, BC, Canada
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), .22 QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Bench PCP, 6mm Regulated PCP and .257 Unregulated, Three BRods.

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