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Copper Projectile - Raw Material

Copper Projectile - Raw Material

Copper Projectile - Raw Material

(OP)
Greetings,

I am just reaching out to anyone who may have knowledge of the best supplier for raw material rod in pure copper. I need the best pricing. Does anyone have experience in this area? We are going to make projectiles for bullets.

Thanks,

Brent

RE: Copper Projectile - Raw Material

Preface: I have nothing constructive to add to your request. Out of curiosity though, what caliber are you looking at? I've only ever heard of machined copper being used for fairly large sized, high precision rounds.

Aidan McAllister
Metallurgical Engineer

RE: Copper Projectile - Raw Material

(OP)
There is a new company started with a large customer base requesting a unique bullet with unique features for this bullet. Mostly, it is unique geometry that sets it apart, but another request is that it be pure copper. The entire projectile will be machined. I am looking at quoting .375 and .500 diameters for 9 mm through 45 cal. I am hunting for a good raw material resource. Currently getting quotes from many, but did not think it would hurt to toss a note out here and see if anyone deals with copper rounds.

Thanks,

Brent

RE: Copper Projectile - Raw Material

Why don't you check out impact extruders? They can source the material better than you, most likely, and save a bunch of time in machining. If you've got some fair volume, they will be pretty cheap.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

RE: Copper Projectile - Raw Material

What d they mean by "pure" copper? Nothing is 100% pure. Do they specify a grade?

I would also question the rationale behind the "pure" spec. Surely there is an alloy with more suitable mechanical properties.

RE: Copper Projectile - Raw Material

(OP)
TheTick - Pure copper meaning C11000, which is 99.9% copper. This is a grade currently in use for certain hunting, long range, bullet splits to 4 paths for a better kill %. There are also self-defense and police tactical bullets that will be produced from these as well, most all with the 4 path once bullet engages its target.

Ornerynorsk, I will check impact extruders out. Thanks for the info.

RE: Copper Projectile - Raw Material

Seems like the point of a hollow-point... shredding head. Been around longer than I have, and no need for "pure" copper...

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Copper Projectile - Raw Material

Copper.org only lists about a bazillion copper alloys, most of which are easier to machine than pure-ish copper, and some of which are readily available in bar stock of the size you want.
Some research there, and discussion with your metal suppliers, should help you propose a few alloys that will be easier to deal with for you, and may better meet your customer's actual requirements, which seem a little fuzzy, so to speak.

Mike Halloran
Pembroke Pines, FL, USA

RE: Copper Projectile - Raw Material

Here is a high purity copper supplier. What is the theory behind needing 100% pure copper as opposed to 99.9% or 99.99% pure copper? https://www.alibaba.com/product-detail/factory-sal...

You said you'd like to "make projectiles for bullets". I'd like to point out that bullets ARE projectiles. They are the projectile component of a fixed ammunition cartridge.

RE: Copper Projectile - Raw Material

"...Pure copper meaning C11000, which is 99.9% copper..." sounds like a waste of "pure" copper for the intended purposes. All bullets that I have bought over the years for reloading purpose were copper clad.

RE: Copper Projectile - Raw Material

Chicopee, solid copper bullets are a thing. It's the terminal performance that greatly differentiates them from other materials.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

RE: Copper Projectile - Raw Material

Solid copper projectiles are used for a number of reasons.
-They are easier to make than a copper-jacketed lead-core bullet. Less overhead required.
-The solid copper projectiles expand with more consistency than lead-core bullets that have copper jackets. (allowing design features that would potentially hinder a lead-core copper-jacket bullet)
-They don't fragment as badly when impacting bone or intermediate materials like denim.
-Some jurisdictions restrict the use of lead-projectiles

Solid copper projectiles have a lower cross-sectional density, so a bullet for a given caliber will be longer than if it were lead-core and equal in mass. This allows a shape that has more gradual curves and better ballistic coefficient without sacrificing velocity. It also allows for a projectile that deforms to a larger cross-sectional area when it impacts the target. Again, all without sacrificing velocity.

RE: Copper Projectile - Raw Material

IF, you are going to make 0.224", I would like a few round nose for a miniature "dangerous game Kynoch" 223 load for my Ruger African

RE: Copper Projectile - Raw Material

Quote (dirtjumpordie)

Solid copper projectiles are used for a number of reasons.

I don't think anyone is questioning solid vs. jacketed projectiles.. the question is why use pure copper vs. an alloy that would be cheaper to source and easier to machine with no performance cost.

RE: Copper Projectile - Raw Material

Shooters have also been known to use bronze, bismuth, brass, tin, and yes, even the proverbial silver bullets. It's no different than any other area of interest. Experimentation with different materials to observe their performance and outcome. The question is not why, it's "why not".

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

RE: Copper Projectile - Raw Material

Pure copper is _extremely_ ductile, which is partly why it's difficult to machine.

But the intent seems to be to make frangible bullets, by a process that is not revealed nor apparent.

Last time I understood the subject, frangible bullets were made by a compaction process, not by subtractive machining. ... and ATF, etc., were trying hard to control the supply chain.

Once again, there are a few things I don't understand.



Mike Halloran
Pembroke Pines, FL, USA

RE: Copper Projectile - Raw Material

Yes, frangibles generally do start off with powder/granular feedstock and are compacted to some degree of incomplete cohesion. They are more for airborne security and sensitive area applications than what a solid would be appropriate for. I think the OP is going after maximum wound channel and controlled distortion, not disintegration.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

RE: Copper Projectile - Raw Material

Distortion, I get.
Splitting into four sub-projectiles, I don't get, not in the requested alloy.
The word 'split' suggests something like saw-cutting the bullet, which would be a LOT easier with something like 330 brass.

Mike Halloran
Pembroke Pines, FL, USA

RE: Copper Projectile - Raw Material

Quote (ornerynorsk)

The question is not why, it's "why not".

...............because pure copper is hard to source in useable stock sizes, difficult to machine, and offers no performance benefit compared to other alloys which have neither of those problems.

It's also highly ductile and likely to foul rifling at a high rate.

RE: Copper Projectile - Raw Material

Hard to source . . . you're kidding right??? As far as performance benefit/ductility, perhaps this is the actual property that is being sought that other alloys may not have. If I understand the OP's intent correctly, this is precisely why some other manufacturers use copper in a fragmenting/segmenting type of projectile. Fouling is not a primary concern in defensive and high lethality rounds, and even at that, can be mitigated through several means.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

RE: Copper Projectile - Raw Material

I suspect that electrical grade copper might work well in this application.

I am concerned that a solid 'pure copper' bullet would excessively deform/distort when fired thru a steel-rifled barrel under normal chamber pressures. Bullet distortion will lead to an unbalanced spin and de-stabilize the projectile. Distortion may be less of an issue, IF: this bullet will be fired thru a 'smooth-bore gun barrel', or if an obturator band is employed to spin-it-up while avoid raw bullet sliding-friction contact with barrel-rifling

Perhaps a hybrid bullet could be made using a bronze jacket swaged/brazed over a pure-solid copper core.... or a pure-sintered copper core. OR sinter/flame-spray a bronze alloy to the exterior of a pure copper bullet.... including the base.

I think Cu-Be alloy was used as a heat shield material in early ballistic missile tests... until other materials evolved into much lighter heat-shields for warheads.



Regards, Wil Taylor

o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: Copper Projectile - Raw Material

Quote (dirtjumpordie)

Solid copper projectiles have a lower cross-sectional density, so a bullet for a given caliber will be longer than if it were lead-core and equal in mass. This allows a shape that has more gradual curves and better ballistic coefficient without sacrificing velocity. It also allows for a projectile that deforms to a larger cross-sectional area when it impacts the target. Again, all without sacrificing velocity.

All of this being true without requiring the rifle be specifically chambered for this longer bullet? Unless there is sufficient room in the jacket to simply seat the bullet further without running out of room for the charge? Just a point of curiosity, I don't have anything to add.

RE: Copper Projectile - Raw Material

""o-ring" is short for obturating-ring"

I'm tempted to think that is coincidence, as I've never heard one used in place of the other. One major distinction is that the obturator band is what spins up the projectile without the sliding friction of full surface contact of the projectile in the barrel. The obturator band is often referred to as the "rotating band" in military specifications.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

RE: Copper Projectile - Raw Material

Changes in projectile length are usually accommodated by changes in the finished press depth of the projectile into the cartridge case.

The case dimensions are important, as is the finished assembly overall length, so that the ammunition will feed properly. How deep the projectile is pressed into the case matters very little, as powders are power dense enough these days that the cartridges are never full.

RE: Copper Projectile - Raw Material

As is often the case in threads like this, the OP has not returned since his initial day of posting...

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Copper Projectile - Raw Material

And Cu bullets in California are EPA compliant. They do not lead to lead poisoning in your adversary;)

RE: Copper Projectile - Raw Material

WKTaylor:
The effects of rifling on a copper bullet would be no different than the deformation on a normal bullet and would have little effect on stability.

jgKRI:
For handloaded rounds for targets I used to set the bullet so that it just engaged the rifling. The rounds were placed into the chamber and could not be fed through a magazine... much too long.

I used to have a 3.7" shell and the steel projectile had a copper band about 1/4" thick by 4" to deform and grip the rifling.

Although toxic, can you use mercury? When I was younger, I made up a bunch of mercury rounds and just incredible expansion... like you'd never believe.

Dik

RE: Copper Projectile - Raw Material

Dik...

Based on my research, the [current] specification for [military] Bullet Jacket cups is ASTM B131 Standard Specification for Copper Alloy Bullet Jacket Cups, which explicitly specifies copper alloy UNS C22000 as 'the standard' for military bullet jackets. I suspect that mot bullet makers conform with the intent of this spec +/-.

Any other copper alloys would require comparable ballistic, wear-testing, etc to ensure internal and external ballistics; and rifling wear-life in [typical] 4140 or 4150-ORD ~HT150 or equivalent 4xx CRES HT150 barrels... bare minimum.

Regards, Wil Taylor

o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: Copper Projectile - Raw Material

Maybe related...

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read FAQ731-376: Eng-Tips.com Forum Policies: Eng-Tips.com Forum Policies to make the best use of these Forums?

RE: Copper Projectile - Raw Material

MadMango: is that from taofledermaus's youtube channel? I know he's tested a bunch of really oddball rounds.

RE: Copper Projectile - Raw Material

BiPolarMoment, no, this was from an article about Franklin Armory and their new Reformation Rifle, having straight rifling and shooting "footballs". A copperclad round here would be very inaccurate I think.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read FAQ731-376: Eng-Tips.com Forum Policies: Eng-Tips.com Forum Policies to make the best use of these Forums?

RE: Copper Projectile - Raw Material

DAVIDSTECKER...

My company web-browser won't let me get anywhere near the Your embedded link... acted like it was 'radioactive'.

Please extract/post a photo or info to the ENGINEERING.com 'attachment' link.

Regards, Wil Taylor

o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: Copper Projectile - Raw Material

DAVIDSTECKER...
How about a link to that square tipped bullet

RE: Copper Projectile - Raw Material

The first post I boned, did you try the second post?
If it still doesn't work, Google Extreme Defender and Extreme Cavitator.

RE: Copper Projectile - Raw Material

Thanks byrdj.
I think some days I spend more time trying to figure out how to use the tools at my disposal than actually using those tools.

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