.308 reloads with split necks.


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Ignition Override
March 14, 2013, 09:34 PM
Naturally they are being thrown out. I've been reloading this for over a year.
The field gauge shows very good headspace: it allows No turning of the bolt handle.

Most cases are from factory ("7.62") Winchester or Hornady .308. The only silver nickel Winchester round used today, which also cracked after my first reload, was originally found at the range, so I used it only once (colored stripe on the case).
Is it normal with full-length resizing to see this after three or four sessions?

The powder loads are always the minimum recommended in the Lee charts, for 165-grain bullets.

Some other cases have been used over six times with no signs of cracks in the neck. Is this typical when always using min. recommended loads of powder such as 4064 or "WC852" Win. Ball Powder ("Similar to H 380"), all data taken from the Lee chart?
Only a small amount of this WC852 is left.

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SlamFire1
March 14, 2013, 09:51 PM
Sometimes new brass will crack at the neck, because brass is not perfect, but I am talking onesies and twosies and not often.

Something else is going on. Have you measured the neck diameter of fired cases and compared with sized cases?

Are you using old military surplus powder? This brass was loaded with surplus IMR 4895 and stored for a year. Upon firing I had a high percentage of case neck cracks and even some case head separations. Old powder outgases NOx and that attacks brass.

As a comparison for how many times you can load and how many case neck cracks you get, I took one set of LC Match 24 firings and 23 reloads used in a M1a. I lubricated the cases and fired them lubricated. Out of 100 cases at the start, the Range Gods hid 55 cases in the weeds. Of the cases I was able to find I never had a case head separation. Around the tenth reload I started keeping track of case neck and body splits. I did have Case Neck Splits ; 1 at the 11 Reload, 1 at 15 R, four at 18R, 2 at 20R, 1 at 21 R. Case body splits occurred with one at the 10th Reload, one at 17R.

http://img.photobucket.com/albums/v479/SlamFire/Reloading/Old%20Gunpowder/IMG_3884Crackedcasenecks_zpse5872a17.jpg

http://img.photobucket.com/albums/v479/SlamFire/Reloading/Old%20Gunpowder/IMG_3879Caseheadcrackedoldpowder_zps9538d9f3.jpg

Trent
March 14, 2013, 09:52 PM
Yes, it's not uncommon to see rifle brass that's full length sized wear out after a few loads.

Cracks form from work hardening. But not generally THAT fast unless it's bad brass or you're working the heck out of it.

You can anneal brass to soften it up - there are threads on here that go in the annealing process in great detail.

Minimum recommended loads can do odd things to your brass, too. If the pressure is low enough that the brass doesn't expand to fill the chamber fully you can get a lot of gas seepage around the neck and down to the shoulder. This can shorten the life of the brass as well.

Make sure when you are full length sizing that you're not shoving the shoulder back too far.

Are you using a bolt action or semi-auto?

If you're using a bolt action I'd change to neck sizing dies - you can get MUCH longer life out of your brass this way.

Also, don't forget to check if the brass needs trimmed. I usually trim my brass to the trim-to-length after the very first firing, and segregate it when it needs it again. When it needs it a third time, it's generally worn out (or time to anneal.)

Trent
March 14, 2013, 09:54 PM
Are you using old military surplus powder? This brass was loaded with surplus IMR 4895 and stored for a year. Upon firing I had a high percentage of case neck cracks and even some case head separations. Old powder outgases NOx and that attacks brass.


Good grief you had a complete head separation with surplus?!!

OldTex
March 14, 2013, 10:00 PM
I was looking at that, too. To heck with the split necks, that stuff is dangerous.

You're making me worry, Slamfire. I've got several jugs of surplus IMR 4895. I never heard of it attacking the brass and basically eating through it. That stuff above looks like it had been fired a few times with some serious headspace issues.

Trent
March 14, 2013, 10:05 PM
Screw that, I have several hundred pounds of 50 BMG pulldown powder I was going to load up this summer, of unknown age. THOSE pictures posted by Slamfire scare the bejeezus out of me.

I can deal with a little head separation in a H&K G3 or a Steyr action bolt gun, they're built pretty tough.

But "head separation" when shooting a bullpup 50 BMG might involve removing MY head. Since.. My head is directly over the chamber of the thing when shooting.

Guess I'll need to REALLY pay attention and proof those loads up.

(EDIT: Sorry for the inadvertent thread jack)

Back to the OP point:

If you're getting split necks that early in brass life, I'd recommend annealing.

OldTex
March 14, 2013, 10:34 PM
The more I think about that surplus powder deal, the more questions I have. I know that the military sometimes uses powder formulations that are not available to the public. But if military IMR 4895 (or whatever name you wanted to give it) did that to brass in just one year, then our military ammo would have a darn short shelf life, wouldn't it? Something is not making sense here. I know too many people who have loaded too much ammo with military surplus powder.

Tolkachi Robotnik
March 14, 2013, 11:06 PM
Father has a big keg of Surplus 4831 left over from WWII. It does best groups of ANYTHING I've tried, and never splits anything. Many years and same story, makes me wonder exactly how they made the stuff.

Only time I've had neck splits like that was with cast bullets and shotgun powders. Brass was not new but maybe I did not have to seat bullets so far down in case, or it split trying to get bullet going. Maybe I should have used more ALOX.

In any event, I recycle any lot of brass that does this sort of thing even if only on one or two necks. Like Trent says (or was it Slamfire said this), it can finally start happening in the teens, and you can expect more of that if you keep using the same lot of brass. Do you have to use that same lot of brass?

I have never had a lower case separation, and don't want any of those ever either.

I would suggest chamber brushing and some attention to throat/necks. Even if trimming cartridge lengths appropriately the necks can get thick and hold the bullets too much as the powder tries to get them going, giving a pressure spike.

Ignition Override
March 15, 2013, 12:08 AM
Correction-the silver Hornady case found at the range was reloaded three times with my gear before it split.
A few of these dozen with neck (only) splits were Nato 7.62 with the tiny 'cross' from an ammo belt I bought, and some were used five-seven times.

The powder for my 165 gr. bullets: 42 grains of 4064, and as the Lee .308 chart shows H 380 (old WC852 Ball Powder: "similar to H-380") only for 180 gr. jacketed bullets (43 gr. powder).

Can't find H 380 powder loads for lighter bullets on this Lee chart. Only in the right column for "180 Gr. Jacketed Bullet". That's why I went down to 41 grains for these lighter bullets, and plan to use the remaining small amount of H 380 powder for my Enfields.

david_r
March 15, 2013, 03:19 AM
FYI,
Speer 13 shows H380 with a 165 and a magnum primer 45.0 - 49.0C
Lee MR #1 shows H380 with a 165 42.8 to 48.0

45lcshooter
March 15, 2013, 06:26 AM
I've had factory ammo split necks and shoulders in my guns and in buddies guns, yes factory ammo. Then I slide a reload in and comes out fine. Some brass they don't make as well as others.

Dave P
March 15, 2013, 07:57 AM
I get a lot of split necks when I shoot my old FAL. I assume it is from a very sloppy chamber.

Trent
March 15, 2013, 08:31 AM
Correction-the silver Hornady case found at the range was reloaded three times with my gear before it split.
A few of these dozen with neck (only) splits were Nato 7.62 with the tiny 'cross' from an ammo belt I bought, and some were used five-seven times.

The powder for my 165 gr. bullets: 42 grains of 4064, and as the Lee .308 chart shows H 380 (old WC852 Ball Powder: "similar to H-380") only for 180 gr. jacketed bullets (43 gr. powder).

Can't find H 380 powder loads for lighter bullets on this Lee chart. Only in the right column for "180 Gr. Jacketed Bullet". That's why I went down to 41 grains for these lighter bullets, and plan to use the remaining small amount of H 380 powder for my Enfields.

42 gr IMR4064 w/ 165gr is "middle of the road".

However, if you're shooting NATO brass, you're probably closer to a max load with that (45gr is max load, and NATO cases cost you a couple grains).

I'd separate out the NATO brass, for sure, and work up a load specifically for it, and keep it separate from the commercial stuff.

SlamFire1
March 15, 2013, 06:29 PM
Screw that, I have several hundred pounds of 50 BMG pulldown powder I was going to load up this summer, of unknown age. THOSE pictures posted by Slamfire scare the bejeezus out of me.

I hate to make good people feel bad, but the reason that powder was surplused was because it was at the end of its shelf life. The US military has ammunition specialists who conduct stockpile surveillance and when gunpowder is too old, and when it gets too old it will spontaneously combust and the burn rate is irregular.

A common test is to put gunpowder in a 150 F oven and see how long it takes to fume the stuff. If it fumes in less than 30 days the powder is scrapped.

Old gunpowder can blow up guns, here is an example of an over pressure account with what was a “known” load:

http://www.thehighroad.org/showpost.php?p=7756780&postcount=6

Although it's remotely possible that a defective load (very unlikely if factory ammo) or poorly stored ammo that had deterioated. I had some H450 go bad and an "accuracy" load from a .30/06 w/180gr bullet locked up the bolt and removed case looked like a belted magnum...... but gun was unharmed.... primer was blown however and pitted the bolt face...... I pulled down the rest of the ammo and powder "stunk" like vinegar and inside of cases were turning green from acid corrosion..... Ammo had only been loaded 6mos earlier... and powder looked and smelled "ok" then.

I have been posting about this and here are a number of posts on this topic:

http://www.thehighroad.org/showpost.php?p=6557153&postcount=25

http://www.thehighroad.org/showthread.php?t=676430&highlight=old+gunpowder

http://www.thehighroad.org/showthread.php?t=692860&highlight=old+gunpowder

This are charts from a 1969 and 1970 safety report. You can see that 40 years ago the military was dumping WW2 ammunition because it was fuming.

http://img.photobucket.com/albums/v479/SlamFire/Reloading/Old%20Gunpowder/1969Ammunitionsurveilliance_zps6bd27200.jpg

http://img.photobucket.com/albums/v479/SlamFire/Reloading/Old%20Gunpowder/1970ammunitionlotsdisposed_zps9776bafa.jpg

BYJO4
March 15, 2013, 06:46 PM
Very interesting thread and information. Those case separations would be a major concern to me and I think would cause me to limit reloading cases to max of 3 times until powder existing powder is used up.

witchhunter
March 15, 2013, 11:39 PM
I would separate the headstamps and pick one to load, maybe the one you have the most of and see if this continues. Something is wrong unless you are using range brass that has unknwn loadings on it before you got it. I like to use only one headstamp for any load in rifles especially.

Trent
March 16, 2013, 09:43 AM
I hate to make good people feel bad, but the reason that powder was surplused was because it was at the end of its shelf life. The US military has ammunition specialists who conduct stockpile surveillance and when gunpowder is too old, and when it gets too old it will spontaneously combust and the burn rate is irregular.


Well, I'm not out THAT much money. Only in to that powder for about $4 a pound.

I think I feel the "mother of all bonfires" coming on this Spring.

:)

SlamFire1
March 16, 2013, 12:18 PM
Originally Posted by SlamFire1
I hate to make good people feel bad, but the reason that powder was surplused was because it was at the end of its shelf life. The US military has ammunition specialists who conduct stockpile surveillance and when gunpowder is too old, and when it gets too old it will spontaneously combust and the burn rate is irregular.

Well, I'm not out THAT much money. Only in to that powder for about $4 a pound.

I think I feel the "mother of all bonfires" coming on this Spring.

Let me recommend you take your time and not act too hastily.

Does your powder have a neutral smell? If it does it won’t be long for this world but it may be useable if you use it up quickly and don’t let loaded ammunition sit around.

Load up some cases and set them aside for a year. Shoot them and if you get an unusually number of cracked case necks, the stuff is bad. This is what I did.

You can load old powder and shoot it up if you shoot it quickly. If you get “funny” retorts and sticking extraction, pour it out.

I bought bunches of surplus IMR 4895 before knowing the kinetics of decay. But since then I decided to work on shooting up the surplus powder. I got through almost 16 pounds of one lot, but now, cases loaded with the stuff are developing an excessive number of cracked necks. The stuff shot great though.

An earlier lot I got cracked case necks, “funny” retorts and the occasional sticking case. The powder shot great but I poured it out.

The first lot of IMR 4895 to go bad, when I opened the bottle reddish dust came out and the smell was extremely bitter. I gave the keg to a machine gunner, thought I was doing him a favor with free powder. He put the bottle in the laundry room of the house. He told me it was on the floor when he tossed some underwear in the room. One set of cottons landed on top of the bottle. Some time later he picked up the underwear and there were holes in the shorts! That disturbed my friend so much he poured that powder out.

Trent
March 16, 2013, 12:48 PM
Those kegs of 50 BMG powder I have (last I checked on it in Dec, it's in climate controlled storage), smelled normal. No bitter/acidic smell. I've had H1000 go south on me before, so I have a pretty good idea of what to sniff for.

SlamFire1
March 16, 2013, 08:03 PM
Cool temperatures are good. The cooler the better, I was told that Artric conditions, unchanging cold and totally dry were the best storage conditions.

I have seen data from DTIC that indicates that when powder is stored at constant temperatures above 90 F the lifetime goes down from decades to years, above 100F, years to months, and around 140 F, months to weeks.

Trent
March 17, 2013, 12:04 AM
It's stored in a basement, sealed heavy cardboard drums, temperature never gets out of the 70's.

I stopped by and smelled it tonight. :)

It smells fine.

Trent
March 17, 2013, 12:06 AM
I have seen data from DTIC that indicates that when powder is stored at constant temperatures above 90 F the lifetime goes down from decades to years, above 100F, years to months, and around 140 F, months to weeks.

Yup, I have seen similar data, in a thread on this board, at one point in time. I think it was a thread on leaving powder in a vehicle (e.g. loaded ammo in a trunk of a car).

This is why I'm picky about which geographic regions I buy ammo from. E.g. no Persian surplus ammo. But Swiss is fine. :)

Maj Dad
March 17, 2013, 12:12 AM
I have tried to buy surplused versus pull-down powder for these reasons. Of course, the powder could have been sold for those reasons, too, but at least there's a better chance it was just excess to requirements. And some of the pull-down was pulled for reasons other than decaying powder, but I still feel better with surplus. Probably a fool's something or other (insert parable/bromide here :rolleyes: )

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