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Old November 9, 2010, 01:05 PM   #1
Boweevil23
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308 case Necks Splitting

New member here, first post, please bear with me.
When I quit competeing in NRA across-the-course High Power rifle matches almost 20 years ago, I had several hundred loaded cartridges of various loads and just left them in my reloading shed. All 308, mostly loaded with 168 gr Sierra BTHP, 40.5 gr of 4895, Win primers, Federal brass. Bolt gun, rapid fire ammo. All twice reloaded, full length re-sized in between loadings. All always shot in the same bolt gun (Rem 700 with Douglas barrell). The gun chamber measures "0" with a "Moe's" guage and I was resizeing to "-.002".
I decided to put my target scope on the gun and do some informal target shooting. While at the range and in the process of sighting in the scope I shot seven rounds without looking at the fired brass, only concentrating on the target and scope sdjustments. As I took the eighth round out I happened to glance at it and the complete neck was gone. I then examined the preceeding seven and on each the neck had split lengthwise all the way from the mouth to the shoulder, some had two splits. Some had also split horizontally partially around the neck/shoulder juncture. Luckily when I raised the muzzle of the rifle the missing case neck fell out of the chamber.
I have loaded and fired many thousand rounds of this same load combination and never had so much as a missfire. The only variable I can think of is the ammo being stored in an uncontrolled environment for almost 20 years.
Has anyone had a similar experience or have any thoughts on what might have caused these case necks to split? Does the work hardned necks, plus summer heat/winter cold, plus 20 years of age equate to some referance that I have not read? Thanks to all you experts in advance.
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Old November 9, 2010, 03:54 PM   #2
Poodleshooter
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Quote:
Has anyone had a similar experience or have any thoughts on what might have caused these case necks to split? Does the work hardned necks, plus summer heat/winter cold, plus 20 years of age equate to some referance that I have not read?
Brass age hardens. Supposedly it's more of a problem with brass that was improperly annealed to start with (Turkish 8mm sucks!),but I'd bet that 2x fired brass is going to be harder and more split prone than the most poorly annealed factory brass.

The solution to this is to shoot and reload more frequently.
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Old November 9, 2010, 04:14 PM   #3
mehavey
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Quote:
Does the work hardned necks, plus summer heat/winter cold, plus 20 years of age equate to some referance that I have not read?
Given I'm shooting HXP vintage 68/70/72 with no problems at all, I don't believe you're experiencing any inherent effects of a storage problem on good brass aging. (And I'm also shooting some 243Win/7mm BR that I loaded in 1989 with no problem as well.) Moreover, two moderate-pressure reloadings shouldn't work-harden anything to the extent that things come apart on you as you described.

You ARE, however, looking at badly anealed brass coming out of the [Federal] factory in my opinion, that moderate aging took over the hill. The solution isn't pretty.
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Old November 9, 2010, 04:20 PM   #4
TATER
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Knee jerk reaction is Yes, twenty years of extremes. I would say pull the rest down
and recover your 168 pills.

I remember gett’en some Surplus .308 in the 90s from Chile, The boxes were falling
apart from years of unknown storage. I was unaware that they were rupturing and the
heads were splitting, One split at the primmer and across the web on both sides. That one
Got my attention as I had to pickup the spring, follower and remaining rounds from the dirt.
Nasty stuff,
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Old November 9, 2010, 04:50 PM   #5
Brian Pfleuger
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Wow! No stretching on the Norma brass for 17 load cycles! Holy Smokes! Add that to the list of reason I use it!
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Old November 9, 2010, 05:19 PM   #6
TATER
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In my mind, I was look’en inside the case...I should have said across the Face and not web. Sorry


Quote:
I remember gett’en some Surplus .308 in the 90s from Chile, The boxes were falling
apart from years of unknown storage. I was unaware that they were rupturing and the
heads were splitting, One split at the primmer and across the web on both sides. That one
Got my attention as I had to pickup the spring, follower and remaining rounds from the dirt.
Nasty stuff,
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Old November 9, 2010, 07:19 PM   #7
Slamfire
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I find it interesting that absolutely no one is suggesting that your powder has gone bad. Almost all the reloaders out there believe that gun powder has an infinite storage life.

Guess what, it does not.

And you stored your ammunition in a shed. Heat is very bad for gunpowder.

Half of all the surplus IMR 4895 I purchased went bad.

The first 16 lbs, I used up eight pounds quickly. For whatever reason, I pulled the bullets on some of that stuff and found green corrosion on the bases of the bullets.

The last eight pounds, it sat around. When I opened the bottle top, it smelled bitter. Red dust flew around.

I gave it to a machine gunner guy. He put it in the laundry room. The bottle got a piece of laundry over it and over night acid gas from the bottle ate holes in the laundry. The guy then poured the stuff out over the lawn.

Since then I have had surplus 4895 powder go bad in the case. Green corrosion on the bottom of the bullets and cracked case necks.

That lot of gunpowder did not have a bitter smell. First I noticed I had a problem was cracked case necks when I shot the stuff. Then case necks cracked in loaded ammunition.

Eventually I pulled the bullet from 700-800 rounds, deprimed the cases, and dumped the cases. I used the primers in blasting ammunition.

I was able to talk to a Navy Energics specialist. He explained that powder deteriorates from the day it leaves the factory. The Nitrocellulose and nitro glycerin want to combine to form a lower energy molecule. Nitric gas is released in the chemical reaction. The rate of combination is directly related to temperature. The higher the temperature the faster the reaction. Powder contains stabilizers. The Navy samples its powders and propellants. If the powder is outgassing nitric gas (as determined by a paper that changes color (Methly Violet test, or Talliani test)), the stuff is tested to see how much stabilizer is left. If the amount is less than or equal to 20%, the lot is scrapped.

The Army does it different. The Army scraps small arms powders by time. Double based powders and ammunition are scrapped at 20 years, single based 45 years.

The military does not talk about this, but bunkers and ammunition storage areas have gone Kaboom due to old powder. That nitric acid builds up, creates heat, and the stuff blows up. It blows up inside the case or the shell.

http://www.liveleak.com/view?i=13c_1205681217

Before the powder goes boom!, that nitric acid gas is attacking your brass. It will cause corrosion on the bottom of bullets, and it will cause stress cracking first on the thinnest, most highly stressed sections of the case. Which happens to be the case necks.

The expert suggested that it is likely that surplus military powders are not on the market anymore due to liability issues. The stuff was scrapped because the military decided it was not safe to keep around anymore.

If the powder has turned red, or smells like acid, it is way beyond its safe limits.

I talked to Alliant powders. They told me that if the plating inside the old cans is has rust spots, the powder is doing that, and the powder should be dumped.

This is worth a look.

http://www.almc.army.mil/alog/issues...t_stab_eq.html
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Old November 9, 2010, 07:39 PM   #8
Edward Horton
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Then the real question is Boweevil23 over the hill or is his ammunition over the hill............................

Or did it have anything to do with storing it in his his reloading shed for so long.

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Old November 9, 2010, 07:43 PM   #9
astorbilt
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Good info.
I may reconsider saving my vintage Lake City .30-06.
Might pull and reload the AP stuff.
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Old November 9, 2010, 10:16 PM   #10
Boweevil23
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308 case Necks Splitting

What a great forum. Knowledgeable people and willing to take the time to share what they have learned. Mr Horton, good charts and picture on brass. Slamfire, excellent explanation of powder deteriation, I think you nailed the problem. All others, informative replys.
I think it's time to start pulling bullets, depriming and chunking brass, even the Lake City "White Box" "Leg Match" stuff I had been hoarding.
I've been shooting since I was 6 (I'm pushing 70 now), military rifle teams, civilian rifle teams and reloading for I can't remember how long and this was the first time I had encountered anything like this. Thanks to all for your assistance.
Boweevil23.
By the way, I had posted this on another forum, had many views but not a single reply. I KNOW what forum I'll put confidence in from now on.
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Old May 8, 2014, 09:56 PM   #11
reynolds357
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I know its an old thread. Today, I brought out a box of once fired, full length sized, then loaded with 168 Sierra match kings. .308 Winchester, Federal Gold Medal match brass. The ammo has been stored 7 or 8 years in an ammo can with several boxes loaded on Winchester brass. The Win brass loads are all fine. In the box of Federals, 17 out of 20 case necks are split. What is even more odd is that 4 of the cracks go all the way back to the back of the shoulder and start running around the case.
What in the world caused this?
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Old May 8, 2014, 10:27 PM   #12
Bart B.
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Quote:
As I took the eighth round out I happened to glance at it and the complete neck was gone.
The neck had bonded to the bullet; a dissimilar metal issue. I've seen this happen with 15+ year old handloads. Very high pressures, too. Dragging that case neck down the bore is not nice at all. This can also cause cracked necks as the brass cracks partially initially, but the bond breaks free and the bullet gies out.

Seating old handloads' bullets another .025" often breaks the bond and the ammo may fire normally.
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Old May 8, 2014, 10:55 PM   #13
reynolds357
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This stuff split just sitting in the ammo can. It makes sense that the dissimilar metals corrode and bond to each other. I cant get in my head how that caused the cases to split just sitting in the ammo can. I wonder if Federal uses something in their brass that causes it to be more reactive than other manufacturers? What is even more weird is I have a box of the Federal Gold Medal from the same lot number that was stored in another ammo can. I got it out and it is pristine. Wonder why the handloads cracked and the factory loads did not. I shot the factory loads earlier today. They did not shoot wonderful, but they shot 1.5 minute. Its still a mystery to me.
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Old May 9, 2014, 11:58 AM   #14
Slamfire
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What I wrote in 2010 is basically as true then as it is now. Of course there could be some bonding of the bullet to the case neck, but, there could also be powder deterioration going on.

The shooting community will not acknowledge that powder ages, such irrationality is based on expectations that gunpowder, ammunition, will last forever. Or, at least as long as the shooter, who also expects to last forever. Suggestions contrary to this are ignored as that is something shooters don't want to hear.



As gunpowder deteriorates it releases NOx. One by product of NOx is nitric acid gas. Nitric acid gas attacks and corrodes metals. Brass case necks are highly stressed and given exposure to nitric acid gas coming out of the powder, it makes sense that the case necks will crack.

I loaded an ammo box full of 308 LC match 308 cases with mid nineties AA4064. The stuff has been loaded for a couple of years, maybe three. When I first shot the stuff long range, it shot superbly. I got 197’s, 198’s, with X counts above 50% at 600 yards. Now, as I shoot the stuff my scores are in the low 190’s and low X counts. Something that clued me that things are going wrong in the case was the fact that over half my case necks are split on extraction. My notes indicate 13 cases, 12 cases, etc, have case neck splits.

So I am pulling the bullets from the cases. Some bullets pull easy, others are taking more wacks than normal. What was of most interest was the condition of the bullet bases. Some bases are nice and shiny, but they are in the minority. I stuck two in the clay in the lower picture. The majority of bullets have this tarnished appearance and a surface roughness I can feel. When I rub the bases on my blue jeans I can restore the base to a smooth surface. The powder in the jug smells fine.

I loaded ammunition with this powder and shot it in nice cases in less than two weeks from the time it was reloaded. No case neck splits but I had overpressure extraction troubles. While the cases were LC I was using the last of my old nickel plated WLR, and I have been using CCI #34’s on the other LC cases, so maybe I have a primer problem, but, I have not ruled out pressure problems due to old gunpowder.

Anyway, I am of the opinion that I am seeing issues related to gunpowder aging.


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Last edited by Slamfire; May 9, 2014 at 01:42 PM.
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Old May 9, 2014, 03:05 PM   #15
RC20
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While Slamfires information is very good, I do disagree that we are not aware that there is an agining process.

Many of us have picked up old powder and check it for condition.

Basically we are assessing it to see if it has aged out. Cooler climate of course have an advantage in that it ages more slowly and can last a long time.


I also test older powder loading up 5 and seeing how it performs though if its iffy or small quantities exposed to a lot of air I just pitch.

My brother had some suspect powder that he tried and found out that suspect really meant pitch. He did not go whole hog, first one was a bit odd the second was for sure.

One reason military power was stable is probably the bunkers themselves acted as a temperature buffer being buried. Not a sure thing but a help.
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