BHN of copper compared to our cast bullets ?

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Last Post 25 February 2016

CBA Member

mtngun posted this 24 February 2016

I was curious how the hardness of my 45 BHN cast bullets compared to the hardness of jacketed bullets. Googling turned up a wide range of hardness numbers for copper or gilding metal. Some sources said as low as 35 BHN. If true, that would make my 45 BHN cast bullets stronger than a jacketed bullet ! That didn't seem right. :X

As always, it's best to test and measure stuff yourself rather than rely on internet experts. I didn't have a thick chunk of gilding metal handy but I did have a 30 caliber Barnes X bullet, supposedly made of copper or some soft copper alloy. So I sawed the nose off an X bullet, filed the cut halfway smooth, and ran a BHN test on my homemade tester. 7.9375 mm (5/16") indenter, 150 kg force applied for 30 seconds.

I used a cheap USB microscope to photograph the indentation along side a 100th's of an inch scale. GIMP's pixel measuring function was used to measure the indentation and compare it to the scale. The indentation turned out to be 0.0508” diameter, or 114 BHN. Conclusion: even my 45 BHN cast bullets are still significantly softer than a copper bullet. :(

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Standard Member

onondaga posted this 24 February 2016

http://www.castbulletassoc.org/view_user.php?id=608>mtngun

I am very curious what actual and practical use you have for BHN 45 cast bullets? Are you a Contrary Warrior where the snake swallows the salmon? Lakota definition of the term: https://en.wikipedia.org/wiki/Heyoka>https://en.wikipedia.org/wiki/Heyoka

Gary

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CBA Member

mtngun posted this 24 February 2016

Gary, I may be a contrary warrior :D, but at this point I don't know whether there is an application for 45 BHN cast bullets, and never mind the “practical” part. :D The thought was that they might prove superior for high velocity cast. Testing has been limited and I have not yet reached a conclusion.

It boils down to the question of why cast bullets fail at higher velocities. If they fail due to being softer than jacketed bullets, and somehow getting deformed by mechanical forces on their trip through the barrel, then 45 BHN bullets should help. If they fail due to other things then 45 BHN bullets may not help. Either way I am curious to see how 45 BHN bullets shoot.

Also, many people including myself are being forced to buy store-bought bullet alloy as wheelweight becomes harder to find. Reclaimed shot is one of the least expensive store-bought options and can be heat treated to 45 BHN, or at least my sample did. If reclaimed shot can be substituted for wheelweight, either air-cooled or heat treated, that might be one practical application.

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Standard Member

onondaga posted this 24 February 2016

http://www.castbulletassoc.org/view_user.php?id=608>mtngun

The Contrary Warrior has been depicted in Lakota art with his rifle that shoots BHN45 bullets.

http://s30.photobucket.com/user/rhymeswithwhat/media/contrary%20Warrior_zpseanlgnmx.jpg.html>

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CBA Member

mtngun posted this 24 February 2016

Dang, that looks just like me !:cool:

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Standard Member

onondaga posted this 24 February 2016

http://www.castbulletassoc.org/view_user.php?id=608>mtngun

Reclaimed shot is generally an Antimonial containing lead with various proportions of Antimony for hardness and no additional metals save Lead.

Antimonial Lead hardened to BHN 45 is doable, but it makes fragmentation bullets. A very significant amount of Tin, for example, would be needed to prevent fragmentation and begin to enhance malleability and decrease fragmentation.

Example: my big caliber #2 alloy FNGC bullets will shoot through a fire hydrant, BHN 45 hardened Antimonial bullets will fragment on contact and spray lead with no other effect on a fire hydrant. I am an active fire hydrant hunter, that is pretty contrary too.

Gary

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CBA Member

Ken Campbell Iowa posted this 24 February 2016

hey gary .... it scares me that i believe you about the fire hydrants ...

or i suppose you could shoot coyotes over those dead fire hydrant bait stations ...

ken...we all have a fire hydrant to bear ....

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CBA Member

mtngun posted this 24 February 2016

Gary, conventional wisdom is that arsenic is added to lead shot, in addition to antimony. Arsenic increases surface tension which helps makes the shot rounder. Some MSDS's confirm that arsenic is present but I've yet to run across a shot manufacturer who guarantees a specific formula. In the case of reclaimed shot you'll have different brands of shot mixed together so it's a roll of the dice what you end up with.

I have not seen any evidence of brittleness in any of the bullet alloys that I have used over the years. I don't have access to a Charpy impact tester to quantify brittleness, but I do have a big-ass hammer. :fire Here's the result of 2 hard smacks with the hammer to a heated treated reclaimed shot bullet, approximately 45 BHN. The bullet started out as a spitzer weighing about 56 grains. It now weighs 55.8 grains.

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CBA Member

Ken Campbell Iowa posted this 24 February 2016

heh, i use a dake press to test malleability of my castings ... ranges from ... ” oh, ok ” ... to ” geeezus ! LOOK AT THAT !! ” ...

ken the simplifyer ...

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Standard Member

onondaga posted this 24 February 2016

http://castbulletassoc.org/view_user.php?id=608>mtngun,

You did NOT hit that bullet hard enough with your big ass hammer. My rifle makes bullets hit fire hydrants a lot harder!!!!!! My Bear load hits with 1,500 foot pounds at 200 yards and easily goes through a fire hydrant at 50 yards.

http://castbulletassoc.org/view_user.php?id=40>Ken Campbell Iowa,

Yes, fear the fire hydrant shooter! All body armor is useless against my Bear load. My grandsons do it too. Our rule is: All Bear loads must shoot through a fire hydrant at 50 yards. This rule is related to the incident of getting Bear Spit on my face after 3 vital hits from a 30-30 when I was 16 in 1966. It still took another shot when the spit hit me with my muzzle pressed into his throat . When I was 16, I thought my 30-30 was the most powerful rifle in the world. It wasn't, now I hunt Bear with bigger guns.

Fire Hydrant tested:

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CBA Member

Ken Campbell Iowa posted this 24 February 2016

gary:: colt sauer ... wow, you can post a pic of that anytime ... my brother had one.... maybe just to irritate me ...

maybe all the youths amongst us have never seen one ...

ken

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CBA Member

admiral posted this 25 February 2016

Do you have pic's of the hydrant? I'd like to see that.

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Standard Member

onondaga posted this 25 February 2016

admiral wrote: Do you have pic's of the hydrant? I'd like to see that. That would be evidence. I have no such pictures.

Gary

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Standard Member

onondaga posted this 25 February 2016

Ken Campbell Iowa wrote: gary:: colt sauer ... wow, you can post a pic of that anytime ... my brother had one.... maybe just to irritate me ...

maybe all the youths amongst us have never seen one ...

ken My Sweetheart.. Colt Sauer Grand African, 458 WM. It gets range time regularly with cast loads. Just over 300 rounds last summer. I'm waiting for the weather again. No Bear shot this past season.

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Standard Member

rmrix posted this 25 February 2016

Dead soft Copper = 42 BHN in this source https://en.wikipedia.org/wiki/Listofcopperalloys

Gliding metal on a other source ranges from 46 to 64 BHN

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CBA Member

mtngun posted this 25 February 2016

Gary, thanks for the information on shooting fire hydrants. I'll keep that in mind in case my state ever offers a season on them.

Perhaps you could write up an article on shooting fire hydrants for TFS ?

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CBA Member

mtngun posted this 25 February 2016

rmrix wrote: Dead soft Copper = 42 BHN in this source https://en.wikipedia.org/wiki/List_of_copper_alloys>https://en.wikipedia.org/wiki/Listofcopperalloys

Gliding metal on a other source ranges from 46 to 64 BHNGood info, rmrix. B)

Your page also lists gilding metal at 114 BHN. I don't know for sure what the Barnes bullet is made of, or whether Barnes anneals their bullets after forming them. This http://www.americanrifleman.org/articles/2014/10/20/barnes-x-bullet-25-years-of-premium-performance/>NRA article muddies the water: I started out thinking pure copper was pure copper,” said Brooks. “But in fact there are different grades of copper. Because I couldn't compare it to anything in the shooting industry”€gilding metal wasn't conducive to what I wanted to do”€I had to go to copper processors and talk to their engineers. I learned about grain size, the strengths of different grains and about the molecular lay of the grain. If it's not right, it's like scar tissue in the copper. The lay has to be a certain way for the bullet to open evenly and be strong enough. The engineers taught me, but at that time it was difficult to get the kind of copper we needed. In practice most jacketed or solid copper bullets are probably going to be cold worked, which makes them harder. Your page says that cold-drawn copper can be 100 BHN, in the same ballpark as what I measured.

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CBA Member

mtngun posted this 25 February 2016

Since Gary said I didn't hit the bullet hard enough, I tried again with a sledge hammer. The bullet now weighs 55.5 gr.. That's 99.1% weight retention.

Sorry but I didn't see any fire hydrants around to shoot. The local authorities kind of frown on that anyway.

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Standard Member

onondaga posted this 25 February 2016

http://castbulletassoc.org/view_user.php?id=608>mtngun

You got your bullet flatter, it has taken you a number of hits to do that. The bullet has visible cracks opening up. You still aren't close to 1500 foot pounds all at once hitting a fire hydrant that would cause 100% weight loss as your bullet sprays into the air because it is too brittle at BHN45. If your bullet was pure dead soft malleable it would flatten to a sheet with zero weight loss from your hammer hitting.

The #2 alloy bullets I use also maintain 100% weight due to malleability with 5% Tin and added strength with 5% Antimony. Lyman optimized strength and malleability for hunting bullets with their #2 alloy over 100 years ago and it hasn't been improved on yet.

I'm still suggesting you try some of the real stuff from a certified supply. My gas checked 22 cal bullets in #2 alloy hold up at 2550 fps but begin to lose accuracy at ~2300 fps from my single shot Ultra Varmint Handi Rifle.

If you are trying to get varmint 22 cast bullets at that speed, try what I do instead of loading up with hardness. Just get a #2 alloy gas checked bullet fit to the throat of your rifle. I have tried Linotype at the same load level and it gets shaved by my rifling because it is brittle, leads up my bore and shoots all over the place.

Gary

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Standard Member

onondaga posted this 25 February 2016

You guys looking at the wood on my Sauer... It is African Bubinga with Rosewood for-end and grip caps. Grip cap has a nice mustang Colt inlay. Bubinga wood is also used by Buck Knife company for the grips of the older folding hunter and their top end Kalinga sheath knives. It is a dense, heavy hardwood, generally straight grained.

I do brag on that rifle! It is known as the finest production sporting rifle ever made. I could never have afforded it and got it in barter for extensive electrical repair on a lightening struck 40' sail racing yacht. I replaced full harness, switching battery set, accessory harness, communications and navigation. His estimates went 4-7k$, I took the rifle instead with a nice airline case and 100 rounds Browning Safari Ammo. I got the extended rings from a collector and added a 4” relief 1.5 - 4.5x scope.

Gary