unused old brass

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cord240

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Help! I have fireformed NEW 12 year old Win brass. It fireformed allright but when using normal loads the cases are not sealing in the chamber. Can brass simply age and lose its elasticity?
 
cord240 said:
Help! I have fireformed NEW 12 year old Win brass. It fireformed allright but when using normal loads the cases are not sealing in the chamber. Can brass simply age and lose its elasticity?
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Unless subjected to some anomaly, (fire, extreme corrosion), the answer is no.

Some surplus military brass is older than many of us on this Forum, and still performs within specs.
 
12 yrs ago created a wildcat cartridge based on the 22-250. Opened the neck to 6mm with a 30 degree shoulder. Purchased 500 rnds Win 22-250. Fireformed 400 to the wildcat cartridge. Performed well. Just recently got into 600yd benchrest and tried the wildcat. Believed fresh brass would be a good thing for 600yd competition and fireformed the remaining 100 rnds. Fireform went well; didn't notice any anomalies in the brass.
Started using the new brass in Matches and noticed powder soot on the cases after extraction. Accuracy went to hell. Initially thought I had somehow under-loaded the powder charge. Checked out ok. Then a fellow benchrest shooter suggested the brass may have lost its elasticity simply by sitting around. Maybe the problem was trying to be cheap and not using good brass i.e. Norma or Lapua. Comments?
 
i find it hard to believe. i have seen 45 acp brass from the 40's still in use.

are you sure your powder charge is in the "normal" pressure range ?
low pressure, poor expansion, soot on cases
 
Could you possibly attach a photo or describe how the case/soot looks a little better. A photo would be best!
 
"Boyd Allen


Yes, brass can harden over time. Believe your eyes."

Yes, yes, yes I agree with Boyd. There has even been articles written about it. I have experienced it with new/unused .222 Rem Mag brass.

John S
 
brass

mwezell said:
I've seen it. It's real.
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The govt. checked the other end, the head, head hardness, after each draw . On a Rockwell. There were 3 draw operations. They went thru a furnace before each draw. Then they went thru body anneal and mouth anneal so the cases got heated up about 5 times that changes the hardness but that was back in the old days. I wouldn't think 12 year old brass would crack if it was in spec on anneals. Doug
 
Doug Casner said:
The govt. checked the other end, the head, head hardness, after each draw . On a Rockwell. There were 3 draw operations. They went thru a furnace before each draw. Then they went thru body anneal and mouth anneal so the cases got heated up about 5 times that changes the hardness but that was back in the old days. I wouldn't think 12 year old brass would crack if it was in spec on anneals. Doug
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I don't know but I doubt 12 years would be long enough to see appreciable problems..of course there are other factors, like how many times the brass has been sized and fired, and how much neck tension.

But, I've seen this problem occur on two different occasions. Both were with Norma brass that was 40+/- years old. One was a 220 Swift that a close friend(actually my uncle) owns, still. He had the rifle built, loaded for and shot a fair amount..then, like many, was put away for years. The brass would split virtually every case upon firing, in the same chamber, on the same rifle as gave no problems back then. This was ammo that had been loaded long ago. He also had empty brass that I tried to load. Most every case split during sizing or firing. It had never done this prior to putting the gun, brass and ammo in a safe for around 40 years. I annealed the necks on some of what didn't split...split necks stopped, then and there.

The other rifle/brass was a similar story, but IIRC, was a 22-250. Same thing...old brass splitting necks. Annealed...splitting necks stopped then and there.

Another analogy is copper tubing. Fresh, new tubing is very soft and pliable. Store it for several years and see how it bends.
 
brass

Yea Mike, I wasn't trying to quote you I just forgot where the button was at to just reply. Ive shot old brass that cracked and newer brass that cracked. Idont know what causes it. Makes me think it was to brittle when it left the factory. I necked down some old .30 cal lake city brass to .270 that was Korean war vintage and it didn't crack and Ive shot fairly new stuff that cracked. I don't know. Doug
 
Doug Casner said:
Yea Mike, I wasn't trying to quote you I just forgot where the button was at to just reply. Ive shot old brass that cracked and newer brass that cracked. Idont know what causes it. Makes me think it was to brittle when it left the factory. I necked down some old .30 cal lake city brass to .270 that was Korean war vintage and it didn't crack and Ive shot fairly new stuff that cracked. I don't know. Doug
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It's ok. I can't prove it happens but I'm convinced that it does.
 
People who study this phenomenon for a living (metallurgists) will tell you that some copper alloys do indeed undergo precipitation hardening (age hardening), a few at relatively low temperatures. Cartridge brass is NOT one of those alloys. I'm not a metallurgist, but I did study cartridge brass in metallurgy classes as part of my formal education

There is anecdotal evidence that old cases crack after sizing and/or firing as well as anecdotal evidence that old brass does NOT suffer such failure. In other words, when it comes to old brass, some say they've experienced cracking and some say they haven't.

I don't doubt either of these reports, but I have doubts that cracking of old brass (if any) is caused by age hardening.

There are documented cases of old loaded ammunition undergoing stress corrosion cracking (season cracking) under the influence of chemical attack, usually by ammonia. And we all know about cracks caused by work hardening as a byproduct of sizing/firing. But as far as I know, there is no documented case of cartridge brass undergoing significant age hardening.

I do not have any experience loading old brass or firing really old ammunition; however, I have studied age hardening in a scientific way and I'm in agreement with the metal experts who say cartridge brass alloys don't get harder by simply sitting on the shelf for a long while. They may be too hard for some other reason, but I'm convinced that just sitting there won't make cases harder.
 
mwezell said:
I don't know but I doubt 12 years would be long enough to see appreciable problems..of course there are other factors, like how many times the brass has been sized and fired, and how much neck tension.

But, I've seen this problem occur on two different occasions. Both were with Norma brass that was 40+/- years old. One was a 220 Swift that a close friend(actually my uncle) owns, still. He had the rifle built, loaded for and shot a fair amount..then, like many, was put away for years. The brass would split virtually every case upon firing, in the same chamber, on the same rifle as gave no problems back then. This was ammo that had been loaded long ago. He also had empty brass that I tried to load. Most every case split during sizing or firing. It had never done this prior to putting the gun, brass and ammo in a safe for around 40 years. I annealed the necks on some of what didn't split...split necks stopped, then and there.

The other rifle/brass was a similar story, but IIRC, was a 22-250. Same thing...old brass splitting necks. Annealed...splitting necks stopped then and there.

Another analogy is copper tubing. Fresh, new tubing is very soft and pliable. Store it for several years and see how it bends.
Click to expand...

When I have cases that do not seal the chamber I always trace the cause to a loose barrel; meaning the diameter of the bore is too large for the bullet. And then there is slow powder; after that there is low pressure. When forming wildcats I choose to form the case once meaning I use a powder that is fast enough to snap the case out to form to the chamber; and no, when I form cases the shoulder does not move; if the shoulder moves while forming I have to start over. The reason for that is only know to me.

F. Guffey
 
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Stress Corrosion Cracking............

Where's "Larry(old bald guy)"..?

Anyway, I have had brand new brass, neck-turned once fired, then reloaded, and sat for about four years. The ones that hadn't cracked while
sitting, cracked on firing, and the two that DIDN'T crack on firing, the necks snapped off when I held a moist patch in my fingers and twisted the case to clean the outside of the neck.

It USUALLY doesn't crack while sitting, but I've seen milsurp that had cracked during storage. Ammonia is also generated during the combustion process, and the brass cleaning fluids used for cleaning brass in ultrasonic cleaners will extract this in about 20 minutes or so, painlessly.

AND, I'm sure someone can come up with a frugal combination that will eliminate the necessity of purchasing the commercial mix, using something like 2oz. pulverized ladybug wings pulsed in a Cuisinart with 14 oz. butterfly proboscides folded into a 30/60/10 mixture of ruby-throated hummingbird/Indonesian Rainforest Vampire Bat guano and water allowed to age for two days in your favorite SunTea container (kept moist), then centrifuged at 2500rpm for 1/2hr., then forced through a 200 mesh and combined w/the recipe of 1/4oz. of the Lyman brass cleaner fluid to 40 pts water.

This will accelerate the scrubbing action to less than 30 seconds, instead of 20-25 minutes, leaving the brass cleaner than clean (sunglasses recommended for viewing), with only slightly more effort on the part of the shooter/hobbyist; but will absolutely AMAZE your competitors on the line.
There WILL, of course, be rules passed at the next br conflab concerning unfair deliberate lasering of competitors eyes while loading/unloading unfairly clean cases, so use at your own peril.....:cool:
 
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