Is US factory ammo intentionally made with one-use brass?

[BattleRife]

Sold as new, unfired brass. It appeared to be absolutely mint when I got it but it failed repeatedly during load development so I ended up tossing it all. Made by Metallverken. They are apparently still selling it. I can imagine the results from an inclusion in the case head, bad to catastrophic...

Did you save any examples? I would like to have a look at one, if possible.

I am skeptical of the theory of non-metallic inclusions. The process of deep drawing a punched cup into a long, thin-walled case is very intolerant of inclusions of any significant size, even a single NMI big enough to extend through a significant portion of the wall thickness would wreck all hell. The idea that they were able to successfully form a case with 3 big inclusions in a row seems far fetched.

 

[B]

What I am calling inclusions seem to be unalloyed pieces of pure copper. The worst failures seem to be clearly from that. I was also getting splits and cracks that weren't obviously from that same issue. I still have all the ####ty brass somewhere in my scrap buckets.

 

[steelgray]

I have finished my specific gravity testing of various commercial cartridge cases. I am very confident in the accuracy of my measurements and the validity of the test method used. If you doubt these, you are welcome to do your own tests – which can easily be done by anyone with a reloading scale, a water vessel and the level of skill that any reloader will possess. The method is covered here (CLICK ON LINK).

The results that I just got seem to make perfect sense for the findings of density that I got for commercial Brass cases from WW-Super, FC and Imperial. As shown in the table below, these all seem to be made of Brass comprised of the two conventional components – Copper and Zinc. I have found that the Imperial and FC cases have a density that suggests these are an alloy of about 80-85% Copper and 20-15% Zinc – which mean that these are made of an alloy which is less than the quality of cartridge Brass. Cartridge Brass is supposed to have 30% Zinc – and it is the Zinc that gives strength to a Brass alloy. Accordingly, these two cases can be expected to be softer and more easily torn (as with head separations) than would be the situation if cartridge quality Brass had been used.

The story is a bit better for the WW-Super case I tested. This had a density or “specific gravity” of 8.85 – meaning it seems to me made from an alloy of 75% Copper and 25% Zinc. Better, but still not up to standard grade.

Then comes the real “headscratcher”. Using exactly the same test methods, with the same test equipment, on the same day I got a specific gravity number for the Herters case of 10.1! That seems to suggest that it's not a common Brass alloy at all. This is evident because pure Copper has an SG of 8.93 and Zinc has an SG has an SG of 7.135 – so regardless of what you try, you can’t blend Copper and Zinc together to get an SG of 10.1!

You CAN alloy Copper and Tungsten together and since the SG of Tungsten is 19.25 the specific gravity of Copper-Tungsten alloys can easily exceed 10.

More specifically, I think that the table below could represent the situation where the three North American cases may be made of Brass and the Herters case could be made of some Copper-Tungsten alloy.

There are lots of good folks in this thread who seem to have a good knowledge of metallurgy so maybe they can add their thoughts to this.

I will note that the pictures I have found on the web of Copper-Tungsten alloy products seem to suggest that such alloys have the same unusual colour as one finds with Herter’s cartridge cases, as show:

Comments will be welcomed.

 

[I Dont Care About You]

Comments will be welcomed.

Somehow I doubt that.

I have finished my specific gravity testing of various commercial cartridge cases. I am very confident in the accuracy of my measurements and the validity of the test method used. If you doubt these, you are welcome to do your own tests – which can easily be done by anyone with a reloading scale, a water vessel and the level of skill that any reloader will possess. The method is covered here (CLICK ON LINK).

This SCREAMS Dunning-Kruger to me.

The results that I just got seem to make perfect sense for the findings of density that I got for commercial Brass cases from WW-Super, FC and Imperial.
.... I have found that the Imperial and FC cases have a density that suggests these are an alloy of about 80% Copper and 20% Zinc

Above, you said, "I am very confident in the accuracy of my measurements and the validity of the test method used." and in the next sentence you use the words, "seem to" and "suggests ... about". Those are the terms of uncertainty. If you are VERY CONFIDENT then the results are strongly correlated with a specific alloy and you can list the exact alloy components.

which mean that these are made of an alloy which is less than the quality of cartridge Brass. Cartridge Brass is supposed to have 30% Zinc

"Supposed" to have 30% zinc? So you don't even know the exact proportions of of the alloy typically used in rifle cases? Has it occurred this might be a serious fly in your theory?

The story is a bit better for the WW-Super case I tested. This had a density or “specific gravity” of 8.85 – meaning it seems to me made from an alloy of 75% Copper and 25% Zinc. Better, but still not up to standard grade.

I'd like you to justify the citing of results to two decimal places please. The significance of decimal places is routinely misunderstood and abused by people with no science training.

Then comes the real “headscratcher”. Using exactly the same test methods, with the same test equipment, on the same day I got a specific gravity number for the Herters case of 10.1! That seems to suggest that it's not a common Brass alloy at all. This is evident because pure Copper has an SG of 8.93 and Zinc has an SG has an SG of 7.135 – so regardless of what you try, you can’t blend Copper and Zinc together to get an SG of 10.1!

You CAN alloy Copper and Tungsten together and since the SG of Tungsten is 19.25 the specific gravity of Copper-Tungsten alloys can easily exceed 10.

More specifically, I think that the table below could represent the situation where the three North American cases may be made of Brass and the Herters case could be made of some Copper-Tungsten alloy.

I will note that the pictures I have found on the web of Copper-Tungsten alloy products seem to suggest that such alloys have the same unusual colour as one finds with Herter’s cartridge cases, as show:

Sorry, you get a value outside the expected range ... with a home brewed test, conducted on a tiny number of samples and rather than resampling with a larger number of tests to validate your method, you come up with a wild assertion based on nothing? I'd LOL if it weren't so ridiculous. #dunning-kruger

 

[steelgray]

Do your own testing. It is easy to do the test - just like its easy to criticize, with no sound basis. You'll get the results if you make an honest effort. Please post your results here.

Somehow I doubt that.


This SCREAMS Dunning-Kruger to me.


Above, you said, "I am very confident in the accuracy of my measurements and the validity of the test method used." and in the next sentence you use the words, "seem to" and "suggests ... about". Those are the terms of uncertainty. If you are VERY CONFIDENT then the results are strongly correlated with a specific alloy and you can list the exact alloy components.


"Supposed" to have 30% zinc? So you don't even know the exact proportions of of the alloy typically used in rifle cases? Has it occurred this might be a serious fly in your theory?

I'd like you to justify the citing of results to two decimal places please. The significance of decimal places is routinely misunderstood and abused by people with no science training.

Sorry, you get a value outside the expected range ... with a home brewed test, conducted on a tiny number of samples and rather than resampling with a larger number of tests to validate your method, you come up with a wild assertion based on nothing? I'd LOL if it weren't so ridiculous. #dunning-kruger

 

[Tokay444]

I think it really explains the rise in the amount of folks annealing their brass, trying to get the most out of subpar product. I find Winchester brass lately has been trash. Federal and Hornady so-so. Nosler has been good, but ouch.

You think people anneal because of “sub par” brass? I’ve never loaded anything but Alpha and Lapua, and I anneal every firing, for precision. Nothing else.

 

[Tokay444]

If you’re getting CHS after a couple firings, you’re oversizing your brass.

 

[Janeau]

You anneal brass for one reason - it work harden each time it’s fired in rifle— and multiple resizing.
Annealing make neck tension more uniform and prolong case life ( split ).

Prepped Winchester brass last has long as Alpha or Lapua. It need more steps to uniform it than Lapua or Alpha.
But for the money Lapua & Alpha cost - you can get 3 times the amount of Winchester case.

In this day and age were effort is replaced by money, to get it all chewed ready to go..that why Lapua - Petersen - Alpha exist. Less expensive brass need to be sorted and prepped. Lapua-Petersen - Alpha got part of the prep work done( quality control- more rejects - better tolerances) for you but at high cost.

I have yet to see any of those shoot better in service rifle than Greek military case or Lake City. Those fancy ( Lapua - Alpha) expensive case do not make the cut in semis used in 600 and a 1000 yard competition - be 5.56. 7.62 or 30.06
That should tell you something…

 

[steelgray]

You think people anneal because of “sub par” brass? I’ve never loaded anything but Alpha and Lapua, and I anneal every firing, for precision. Nothing else.

This article (LINK) suggests that some Lapua brass has more than 30% Zinc content - which should make those cases stronger and better than even normal cartridge brass. For those you don't know that cartridge brass is supposed to contain 30% Zinc, have a look at Wikipedia. My testing isn't a "home brewed" method. It is how people have been assaying metals since the Middle Ages.

 

[BattleRife]

I have never before run into copper-tungsten alloys. A quick internet search tells me that copper and tungsten have no mutual solubility, and therefore cannot be alloyed.

Anything on the commercial market as a copper-tungsten material is actually a metal-matrix composite, literally particles of copper in a tungsten mass. I hope it goes without saying that deep-drawing such a material would be virtually impossible.

 

[devolut]

What is the point of this rant?

Brass is what it is and we, the end users, can't do anything about that. You can rant till you turn blue and its not gonna change a damn thing.

You must be fun at parties.

 

[BattleRife]

This article (LINK) suggests that some Lapua brass has more than 30% Zinc content - which should make those cases stronger and better than even normal cartridge brass.

As I stated previously, the article you link has no credibility. I don't suppose you checked out the article I referenced? You know, the one where qualified technicians posted results measured on calibrated equipment, to a published standard?

In case it was just too much effort, I post the pertinent information here:

Note that while a couple of the results fall outside the traditional cartridge brass window of 70% copper +/-1.5%, it is by the smallest of margins.

 

[I Dont Care About You]

Do your own testing. It is easy to do the test - just like its easy to criticize, with no sound basis. You'll get the results if you make an honest effort. Please post your results here.

I don't care about the alloying of brass and its effects on the quality of the resulting cartridge case.

 

[I Dont Care About You]

This article (LINK) suggests that some Lapua brass has more than 30% Zinc content - which should make those cases stronger and better than even normal cartridge brass. For those you don't know that cartridge brass is supposed to contain 30% Zinc, have a look at Wikipedia. My testing isn't a "home brewed" method. It is how people have been assaying metals since the Middle Ages.

OK, you are correct, I didn't mean method, I meant the equipment you are using is kitchen table stuff, completely uncertified or standardized. The error in your measurements could easily be greater than whatever differences you are finding. Have you even calculated the statistical significance and error inherent in your method?

 

[OkayShooter]

OK, you are correct, I didn't mean method, I meant the equipment you are using is kitchen table stuff, completely uncertified or standardized. The error in your measurements could easily be greater than whatever differences you are finding. Have you even calculated the statistical significance and error inherent in your method?

Yup. Kitchen scales are soo accurate. Postal one gave me the same result as the kitchen and I'm not destroying my digital reloading scale, because a cup of water over loads it. Middle ages eh? How many ducks are 1 oz

*Grabs a handful of brass from the brass bin and continues to reload.

 

[steelgray]

I have never before run into copper-tungsten alloys. A quick internet search tells me that copper and tungsten have no mutual solubility, and therefore cannot be alloyed.

Anything on the commercial market as a copper-tungsten material is actually a metal-matrix composite, literally particles of copper in a tungsten mass. I hope it goes without saying that deep-drawing such a material would be virtually impossible.

I was hoping you'd comment because you seem very knowledgeable. There certainly are businesses on the web selling Copper Tungsten alloys (LINK) but I see them mostly supplying the stuff for use in electrical contacts, electrodes etc. I wonder if you have any ideas what alloy could be used to make cartridge cases with a specific gravity of about 10? I'm quite sure of my SG calculations ( I did them multiple times). I just don't know how to interpret them. The Copper Tungsten idea made some sense to me because - as noted - pictures of Copper Tungsten materials seem to show that the stuff has a slight pinky hue - which is a characteristic of my Herters cases (something that many people notice).

Any ideas?

 

[Potashminer]

I did watch that video - the guy did not measure the amount of water displaced - just compared total weight of the ring he tested, the tub of water, then the tub of water with ring suspended in it. I am still working on that idea - as if the ring displaced an amount of water, so the ring had some more weight than the water that it displaced - resulting in greater total weight of the tub. Not sure yet that is what Specific Gravity actually is - I thought S.G. was a particular weight per volume - maybe that was a short cut to get there?

I am still stuck on this procedure to establish Specific Gravity - he has the ring suspended by a string from an overhead rod - so what happens to the weight that is being supported by that rod? I guess I do not understand how that is accounted for? I can imagine how the weight supported by that rod gets to be less, as the object displaces water - but not sure I can follow that ALL the weight came off the supports for the rod? I am most definitely NOT saying that he is in error, but I do not understand what he did to arrive at a S.G. number for that ring.

 

[steelgray]

As I stated previously, the article you link has no credibility. I don't suppose you checked out the article I referenced? You know, the one where qualified technicians posted results measured on calibrated equipment, to a published standard?

In case it was just too much effort, I post the pertinent information here:

Note that while a couple of the results fall outside the traditional cartridge brass window of 70% copper +/-1.5%, it is by the smallest of margins.

This looks like good information. Thanks for sharing. I'm inclined to think that the cartridge cases tested were one sold as new and were intended for reloading.

By comparison, all the ones I have tested - except the Herters ones - were recovered cases from commercially-loaded ammo. I'm inclined to think that - at least for 303 British - the Brass that they use for their loaded ammo is the cheapest stuff they can get away with; quite possibly because the manufacturer has some older forming equipment that they think can still be used legitimately to make cases for a lower pressure round like 303 Br - and where they feel that the customer has no good basis for complaining, if they only get a small number of reloads from the cases recovered - after firing such ammo. I have actually worked in a metal works (Alcan's Kingston Works) and, while we didn't make brass products, I am well aware that - in industry - you take stock of the equipment you have and deploy it in a way that is most profitable. It seems logical to me that, if an ammo manufacture had an old case drawing machine that was on its last legs - and could only productively handle brass with 20% Zinc content, you would deploy that to make cases for loaded 303 British ammo - not 7mm Win mag brass, for sale as new cases.

As for the article, I wasn't there. It says that the technician who ran the tests was experienced in the use of the equipment and was himself a shooter. Lots of articles don't go into all the gritty details of the applicable procedure. This article apparently used to but the link doesn't work.

I get it that there are lots of flat earth society folks out there and many others who just seem to like throwing bombs. I think if anyone reads this thread thoughtfully you'll see that no one is relying one one data point. There is a convergence of observations here, from the article, to my test (which anyone can replicate) through to your print-out and the many, many user observations that have been shared.

My conclusion is that not all brass is created equal. The better stuff will meet the industry standard for "cartridge grade" brass - having typically 30% of more zinc in the alloy and presumably no foreign inclusions, etc. Given the economics involved, you don't need to look to far for brass that does not meet this standard - and I believe it is typically going to have been intentionally used to save a few bucks or extend equipment life etc. when making cartridges for ammo - where all the vendor cares about is that the stuff meets expectations from the first firing. Tim Hortons would feel the same way about their take-out coffee cups. They don't really expect you to keep refilling them - even though they aren't going to stop you - or warn you about how the bottom may fall out after a few repeated uses.

The real losers here are the folks who REALLY DO think that "all brass is the same" and go to extreme lengths trying to extend the life of 303 British cases - that had originally come from fired ammo.

These folks use "O"-rings and neck size only - and get their cases so that they headspace on the shoulder etc. - and still find that the cases of that type die quickly. Then, they get sucked into believing that the problem is that their gun has headspacing problems. Some will waste their time and money on needless trips to the gunsmith - and will have changed their bolt heads multiple times - all without changing things. This is because you have to understand a problem in order to solve it.

People who think that "brass is brass" - and who set themselves up to suffer through trying to get their inherently-fragile, once-fired 303 British cases to last - need to wake-up and smell the coffee; maybe even the coffee in that cheaply-made, one-use-only Tim's cup.

 

[tiriaq]

Do you have access to a set of headspace gauges? It would be interesting to know how your various rifles gauge.

 

[steelgray]

Do you have access to a set of headspace gauges? It would be interesting to know how your various rifles gauge.

Sorry no but I have about 6-7 guns in 303 British and all suggest that I have headspacing problems (meaning that I get those shinny expansion rings on firing full length resized cases) if I use my North American cases commercial, left over from commercially-sold ammo - and none of these 6-7 guns produce those nasty shinny expansion rings with the same loads, shot in the same guns - when I use my Herters brass.

I've got around 80 Herters cases and have fired some 12 times and none have ever exhibited an expansion ring. That's 12 firings by me and I bought these from an unknown original source (through an auction site) when they were already an estimated 30 years old. When I have cut one of these high-use cases open, I didn't see that tell-tale wound on the inside behind the expansion ring - while all three ex-commercial North American ammo cases I have sectioned show that wound (after tiny number of firings). Also, you know that the Mohawk has a reputation - in bubba-guy circles - for "ripping the heads off cases and throwing them an acre away". I hope you enjoy the humous there.

I haven't had any other type of case failure with all 80 or so Herters cases; although a couple did damage themselves from bouncing off the underside of my scope on my semi auto and trashing themselves in the closing action. Guess which Herters cases I choose to section? As for the commercial cases (FC, Imperial, WW-Super, etc.) that presumably started life as a component in commercially-loaded ammo - I've had some fail after three firings.

Things like out-of-the-blue neck separations, neck splits and head separations. I even had one N/A commercial case suffer a full head separation in my case tumbler. I've got some flack over that because it seems impossible but, yup, it happened. I suppose it was so far gone that any extra stress was going to finish it off.

Obviously my headspacing problems didn't cure themselves because I used better brass. The situation is the reverse. If you use junk brass, it is easy to be misled into believing that you have headspacing problems and that myth has, IMO, taken-on a life of its own with the retelling - one generation after another. To me, that s sad because all that crappy NA commercial, brass - recovered from fired commercial ammo - has created a false narrative that there is something terribly wrong with the L-E - and the current generation is reluctant to even try-out one of these wonderful warhorses - even at the prevailing crazy low prices.

Long answer but no, I don't think headspacing gauges would tell me anything based on how my "headspacing problems" disappear with better brass.

BTW I also have an AIA L-E-type gun in 7.62x39. Guess what. That gun doesn't know what an expansion ring - or a head separation is. Yes I know that 7.62x39 headspaces on the rim but if there was something to the sil*y L-E stretchy action story, that probably wouldn't make a difference.