Problem with 22/250 Brass Cracking

[Kevin Rohrer]

About ten years ago I bought 1k, new, bulk 22/250 Winchester brass and am just now reloading it for the first time. The brass is still as shiny as when it arrived. Unfortunately, I am seeing a lot of partial and some complete cracked necks after only one firing.

Out of thirty rounds fired, two have cracked necks and five more have cracks started, all in the middle of the neck. I checked the unfired brass, which measured .249". After firing the necks measure .256" or a bit more. Case neck thickness is .015", which is consistent with what others are reporting.

I haven't had a problem with this rifle (Remington 700 Varminter) in the past, and it has only had about 200-rounds shot thru it.

Upon checking the brass, I can find no signs that they were annealed during manufacture, but my research suggests that manufacturers shine up their cases after annealing, which hides the annealing. I do not size the brass before loading, but do chamfer them to ease bullet seating.

Thinking that this brass is brittle, I have a case annealer on-order and plan to anneal the brass before doing any more loading.

Does anyone have any suggestions as to what might be the problem and/or the solution?

[MtGun44]

Cracked necks is too hard brass, brass only gets hard one way - mechanical working, so it has
been sized too much - however that happened, factory or too many reloads.

Anneal carefully, easy to get too much. However if you get necks too soft, you can size and
expand back and size and expand again a few times to reharden it.

Bill

[Wally]

MtGun44 How do you anneal your brass? I too purchased 500 .22-250 cases in 1985 that I have yet to load/use--they are WW. I best anneal before I use the--I hate the sight of split cases necks...

[wmitty]

I had a problem with split necks years ago with factory (Rem) loaded .22-250 brass. This was well before I knew about annealing brass so I simply switched to Winchester brass and never ran into the problem again. I assumed it was due to excessive hardness in the neck portion of the case as a number of the case necks split upon initial firing of the factory round. Have not seen this problem with Remington or any other make of brass since.

[Kevin Rohrer]

Wally,

All brass is supposedly annealed at the factory before sale, but I have my doubts my brass had it done. My annealer will be here next week and we shall see if the problem disappears.

In the meantime, here are two excellent articles on brass annealing:

http://www.6mmbr.com/annealing.html

http://www.annealingmachines.com/model_360

The second link also shows the annealer I have coming.

[Wally]

Wally,

All brass is supposedly annealed at the factory before sale, but I have my doubts my brass had it done. My annealer will be here next week and we shall see if the problem disappears.

In the meantime, here are two excellent articles on brass annealing:

http://www.6mmbr.com/annealing.html

http://www.annealingmachines.com/model_360

The second link also shows the annealer I have coming.

Thank You

[tomme boy]

I always heard brass age hardens just like lead does. That might be what happened.

[MtGun44]

Brass does not age harden. It can be affected by ammonia and compounds with ammonia
and this will cause stress corrosion cracking, but not due to hardness - due to corrosion
while under high tensile stress.

I have tried several methods of annealing. Heating to faint glow will over anneal in my
experience. Dipping in lead underanneals and leaves lead on the necks. I got good
results with spinning in a deepwell socket on an extension, then a propane torch
and counting to, IIRC, six.

Still working on it, but the last way did good for me that one batch. Not as precise
and repeatable as I would like.

Bill

[Von Gruff]

The deep well socket is the way I go to Bill. I found that is I run the brass through the polisher first and anneal in good bright light I can see the first blue tinged rainbow colouring on the necks easily (anymore is too much) and get repeatable results. I have 7x57 brass that is at least twenty years old with 40 plus firings through it. Last few years it has been plinking loads but initially there were well over twenty full power j-words in a previous 7x57 I had.





Von Gruff.

[Artful]

I'm going to have to disagree that old brass can't get brittle - I've had batches of "factory new"/military surplus ammo that the neck split on firing probably 50% of the time.

I've had brass that was fired with old corrosive primers that affect the brass likewise - split upon resizing.

I do agree with treatment - clean and anneal

[Firebricker]

Kevin, This exact same thing happened to a friend a couple weeks ago. He made a rifle trade with his dad that included three hundred loaded rounds in new brass. Almost every case cracked at bottom of the neck top of shoulder. We pulled bullets and confirmed powder charge and cronographed ten rounds everything checked out. Then we pulled five bullets dumped the powder and replaced it with a reduced load of SR 4759 out the manual. The reduced loads all cracked the same as the others. The brass was new but at least ten to fifteen years old. He sent some cases back to Winchester for them to look at but no word yet its only been a week since they got them. We also fired a few out of two different rifles. FB

[selmerfan]

I had the same problem with a batch of Winchester .243 Win. brass from about ten years ago. Annealing took care of it, but I shouldn't have to anneal factory new brass.

[cajun shooter]

All Starline brass comes with a notice to anneal all case necks before using. I anneal all rifle brass regardless of brand or age. It does not take that long to do plenty of cases. Von Gruff That is a neat set up that you made sir and I tip my hat to you.

[MtGun44]

Not saying that brass can't be brittle when it is old. Just that it didn't get brittle just by
sitting around. Brass can be affected chemically by ammonia compounds and there can
be stress corrosion cracking - a specific phenomena of a corrosive attacking a metal that
is under high stress (very tight boolit in a neck?).

If you take a chunk of brass and measure the hardness and then set it on the shelf for
50 yrs and measure again, it should be the same. I know of no phenomena that causes
brass to age other than chemical attack, specifically with ammonia (rat urine is a common
source in poorly stored ammo) compounds, even at pretty low levels.

If made too hard at the factory, this is probably the issue seen years later. Frankly, making
a cartridge case is an art, and I am in discussion with a BIG ammo supplier to help to
engineer the process from an art to a science to make batches of brass more consistent.
Years ago, it was much worse and some batches were a mess.

If the project goes thru, I'll wind up being deeply involved in the case manufacturing process
and the metallugy and working of cases in a truly scientific manner.

Bill

[Artful]

Well Bill good luck in your new endevor - I'm just going by what I have happen to me - And I remember some military ammo back in the 60's the NRA just flat warned against trying to reload period due to bad barss - But it stands to reason that oxidation on brass and copper is a given and time weakens us all.

[Kevin Rohrer]

Bill,

Are you of the opinion that manufacturers anneal their brass before sale, then polish them, which hides the annealing color; or don't anneal them?

Based on what you say, I either got a bad batch of brass (although I don't know what may have occurred to make them "bad") and/or they were never annealed, which caused them to be so hard they split when fired the first time.

[MtGun44]

Various manufacturers all have different processes. The thing that they are trying to accomplish
is to have the head of the case hard and fine grained, yet not brittle, and the middle portion
a bit less hard, a bit larger grain size and then the shoulder and neck harder than fully annealed,
which is very soft indeed, nearly useless, yet NOT too brittle.

Since heat removes hardness because the grains start to merge and the dislocations sort
themselves out in the metal matrix as heat causes the molecules to bounce around harder
(the definition of heat is atomic motion), you can always soften with heat. HOWEVER, the
ONLY way to harden cartridge brass is to permanently deform it.

So the manufacturer has to balance the ability to remove hardness and the difficulty of
adding it, as he designs his process to go from a slug of brass to a finished case. Tricky
when and where and how much you anneal to keep from cracking the brass as you make
the case (in a MANY step process), yet be certain to wind up with the final shape and the
final amount of work hardening in the various portions of the case.

If one manufacturer does an anneal at the end of the process on the necks, it doesn't
mean that the same manufacturer with a different caliber or a different manufacturer with that
same caliber will not have a different process, different anneals at diff temps and at different
stages in the process. Also note that the term "an anneal" means heating to a certain temp
for a certain time, there can be HUGE differences in the amount of work hardening removed
by "an anneal".

Basically, impossible to say whether a final anneal is always there or if it should be. Also, as
you point out, a final tumble may remove the anneal color changes, so who knows? If most
brass is final annealed on the neck, then I'd say most of it is polished enough afterwards to
remove the colors - why? because most civilian brass does not show anneal colors like
military brass often does.

And any endeavor with people involved will wind up with errors. If brass has 'too hard'
necks right off the bat, it is the fault of the process - either all will be bad if a bad process, or
some good and some bad because the process is inconsistent, time or temp or something
is not being controlled properly, or maybe a batch just missed a step. $#!* happens.

Bill

[snowshooze]

I had the same problem.
As it turns out, the TC Encore Pro Hunter chamber was horribly over depth. After two exchanges with them, I sold the TC barrel and went custom.
Measure a fired case against a new one, and if should tell you if it is way off. With mine, you couldsee it with your bare eyes, nearly .040" over depth on the chamber ream.

[40Super]

I wouldn't doubt some times the factory is plugging away at making brass and the annealing process isn't working like it's suppose to. Maybe they ran out of gas and how many case ran through before they caught it? The cracked necks are from the brass being hard. I've annealed several batches of .243 and 22-250 brass to get a few more reloads out of them. I had an old record player that I took the table off and stuck a piece of pipe on it to stick the brass in. I timed it by a few seconds and had annealing sticks to see what temp the neck was at to set up and just put a new case in hit the timer, grabbed the case out with a needle nose and repeated. Time consuming and the motor got to hot and fried eventually. Haven't done any since, but it did get me a little more use out of most cases.

[Firebricker]

Since this popped back up I will update my post. After he sent the case,s to Win (22-250) they said it was a bad batch and replaced them. Fb