How old is too old for brass cases?

Nosler06

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I have had some neck splitting on my 30-06 brass. Some of the brass has been loaded up to 10-12 loads and is 15-20 yrs old. Probably time to look into new brass I think. Any ideas as to how long brass is good until it becomes hardened or brittle?
 
Depends on how many times you fire it and the conditions its stored in. Shoot your brass until it cracks/splits. If you want to save your current brass and like to spend time as a hobby, anneal your brass, heating it up realigns the particles when it comes brittle. see below video

http://www.youtube.com/watch?v=kgD5D0Wzu-c

Folks I know that do something like this but let it air cool though as opposed to dropping it in water. Air cooling vs rapid water cooling I am not sure if there is any material gain with either method but thats to be looked into when you study the method more in depth
 
I have some that are about 45 years old. They usually get about 20 reloads without annealing before the neck cracks. I throw them out once I see a crack starting.

Annealing will give you more life.
 
The water cooling is just to cool the brass, its not like hardening steel (quenching). Air cooling gets the same result. Also some people stand them in water so the base cannot get softer, just the neck.
 
The water cooling is just to cool the brass, its not like hardening steel (quenching). Air cooling gets the same result. Also some people stand them in water so the base cannot get softer, just the neck.

Yes, and another trick is to just lay them on a damp towel. You want to suck the heat out of them so only the neck and shoulder area is annealed. Putting them on a towel keeps the inside from getting wet and having to be dried before going to the next reloading step.
 
IMHO it does depend on how long the brass is under tension. If you have loaded rounds that have been fired multiple times even if annealed, you may get neck splits. It all depends on the metallurgy of your brass. Brass available at different times has different percentages of copper and tin, which will make them more or less ductile. There are other components as well that will effect this but those seem to be the main ones.

It isn't unusual to open a box of Western Cartridge Company, or milsurp 30-40 Krag/30-06 and find factory loads with split necks. I read an in depth article on this in "Guns" magazine many years ago explaining this phenomenon. To boil it down, if you find factory cases with split necks it is usually either because of an extended period of tension from being stretched around the bullet and or metallurgy.

This will cause problems for hand loaders. Recently, the brass available for extruding is being made to a different standard. This is done for several reasons, usually financial but sometimes just a lack of components. The brass casing is the most expensive part of the cartridge. Governments are the main procurers of ammunition and even though they will reload training ammunition, anything that makes it to the field on exercises or battle, is new. When it gets fired, it usually stays there. I used to love going to the areas the militia had exercises in the field went. 6.5x55 cases were almost impossible to find and the 7.62x51 blanks worked just fine, after cutting them down and fire forming them. I still have some of those cases with at least 50 reloads on them, IVI brass.

IMHO, it makes perfect sense to re anneal after every 5-6 re loadings, sooner if the cases are hard to form. I mostly use a 40 year old RCBS JR press for reloading serious stuff as it is absolutely true to center if the dies are OK. In fact I use it to check out new die sets for true. This press doesn't have nearly as much force as a Rock Chucker, which I like because I can "feel" what's happening. Work hardened brass makes for inaccurate ammunition.

When I was in Brazil about 35 years ago, I went to a metal manufacturing complex in Belo Horizonte', they made everything you can imagine, mostly steel. They also made brass and other metals. One of the buildings that was off to one side, out of the smoke and dust, was a cartridge refinishing factory. I was amazed at what I saw and learned. Some here would roll and scream foul in the aisles, so I won't go into detail. Suffice to say, the raw material was mostly fired brass casings purchased as scrap from their military and police. After cleaning, polishing, inspecting and sorting, all of the brass was annealed. No attempt was made to check dates or amount of firings etc. It was all dumped into huge bins and taken to another factory for depriming, sizing and loading. It was all very impressive and so fast I could hardly follow what was happening. At the reloading plant, the necks were re annealed again, before being loaded, this wasn't done to soften the necks but to harden them enough to create the desired neck tension on the bullets. Big wake up call there. Civilians don't usually worry about that but in a full automatic firearm, it is very important.

IMHO, if you anneal regularly, mark your cases with an indelible marker or keep each batch separated, keep your loads below maximum and trim when needed, your brass will last almost indefinitely. Taking care of casings is far more involved than just trimming, cleaning, uniforming the primer cups and flash holes. It's a very good start, just not quite enough.
 
At the reloading plant, the necks were re annealed again, before being loaded, this wasn't done to soften the necks but to harden them enough to create the desired neck tension on the bullets.

Someone either really misunderstood the reason, the process, or was feeding you a line of hooey!

The only thing you can do to make brass harder, is to work it. Any heating process will only make it soft.

Brass work hardens. If it is worked too much without proper annealing, it splits. If it has been work hardened and worked some more before, say, annealing it prior to running it through the loading equipment at a factory, split necks in a box of old factory ammo are a pretty probable result.
Theories to the contrary, can generally be explained by a total lack of understanding of what goes on when the stuff is worked or heated.

There has been a lot said, about problems with Bertram brass, IIRC, in some circles. Nothing as much fun as finally getting a bag of new brass, otherwise completely unavailable, and losing half or more to splits on the first loading! Yech! Not my experience. I'd never stop telling everyone, if it happened to me! :D
New brass. Can't blame it on sitting for long periods.

Cheers
Trev
 
Any ideas as to how long brass is good until it becomes hardened or brittle?

There is no reason to establish a hard and fast date, as someone else said, the life is a product of how the brass is used and how it is stored.

Neck splits on brass that has been loaded for a long time are almost certainly due to stress corrosion cracking (SCC). The necks are in static tension, and corrosive elements steadily initiate and propagate cracks. When you fire the case, the stress tears the remaining ligament open.

failon6thcrackstart160xas-plabelled.jpg


Annealing can be used on brass when it is not loaded to reduce stress and avoid the occurrence of SCC, but the best approach to preserving loaded ammunition is probably to keep it sealed in an airtight container, or possibly to wash or wipe it down occasionally. SCC is not well understood at the home user level, and none of this stuff has ever been rigorously researched.
 
Brass available at different times has different percentages of copper and tin...

Recently, the brass available for extruding is being made to a different standard...

Do you have any reference for statements like these? It sounds to me like someone has been feeding you a line. The effects of zinc on the malleability of copper have been known for well over a century, and UNS C26000 is called "cartridge brass" for a reason.
 
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