Thoughts on necks starting to split

Hey guys, anyone care to shear their opinion on necks starting to split on two times fired brass.


Rifle was cut to standard Sami spec 7mmSAUM

Loaded neck is .315 fired case is .320

22inch barrel shooting 162gr 3020fps with 61.8gr r26

Gun smith says it probably a case failure.

Cases are on the second fire and are Norma.

Nz ammo want all the brass back to send back for testing, witch will leave me with none for who knows how long. Rifle shoots pretty good so it doesn’t seem to effect accuracy

Attachment 204927Attachment 204928Attachment 204929Attachment 204930

Brass too brittle

Anneal the necks properly to the shoulder junction and try a few again

And graphite powder the neck ID and projectile OD when assembling your ammo to stop galvanic corrosion from gripping the projectile, which sends a nasty shock through the neck upon projectile release

Happened to me with my 22-250 and Norma brass, 2x fired and it shat the bed. Didn't think to hit them up

Anneal every time.

NZ ammo want brass back...no worries,just send me some to use while you get the results back..thanks very muchly...job done.

+1 annealing each time. Might be able to restore unsplit brass with an anneal.

Are you using bushing dies?
If so, are you just sizing .001-.002 under .315 as any smaller will be over working and hardening your necks.
If they are standard dies then remove the expander and see how much the necks are being sized under .315 as some standard factory dies can size the brass way under what you would expect them to before the expander pulls back through.

And you could have got that speed with ADI2217

It’s far more available and temp stable than anything made by Alliant Reloader

Tried and couldn’t get that speed without pressure signs and tight bolt lift, the rifle also seemed to really like r26 and my goal was 162 at or just over 3000fps. If only I can get the brass to hold together

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Originally Posted by Matt2308

Are you using bushing dies?
If so, are you just sizing .001-.002 under .315 as any smaller will be over working and hardening your necks.
If they are standard dies then remove the expander and see how much the necks are being sized under .315 as some standard factory dies can size the brass way under what you would expect them to before the expander pulls back through.

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I’m using Redding comp dies. And full length. I’ll have a play tomorrow and see how much it’s working the brass with/without the expander

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Originally Posted by Micky Duck

NZ ammo want brass back...no worries,just send me some to use while you get the results back..thanks very muchly...job done.

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That would be ideal. But they don’t have any brass in stock

Quote:

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Originally Posted by Matt2308

Are you using bushing dies?
If so, are you just sizing .001-.002 under .315 as any smaller will be over working and hardening your necks.
If they are standard dies then remove the expander and see how much the necks are being sized under .315 as some standard factory dies can size the brass way under what you would expect them to before the expander pulls back through.

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So I have run one through the die without the expander and it comes to 0.308

Quote:

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Originally Posted by dale

So I have run one through the die without the expander and it comes to 0.308

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I don’t like using expander ball for that same reason it works the brass to much and need to change bushing size. I never anneal bass and get somewhere from 7 to 12 firings from 100 pieces of brass. Primer pockets give out before the necks and case wall do.

Quote:

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Originally Posted by dale

So I have run one through the die without the expander and it comes to 0.308

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That’s a heap of extra and un-necessary sizing taking place and is certainly contributing to, if not the cause of your necks splitting.
Bushing dies with a .314 bushing would half the amount you are working your brass and extend its life considerably.

I would definitely suggest annealing every sizing with your current dies, but even this might not be enough to fix the issue.

Quote:

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Originally Posted by Matt2308

That’s a heap of extra and un-necessary sizing taking place and is certainly contributing to, if not the cause of your necks splitting.
Bushing dies with a .314 bushing would half the amount you are working your brass and extend its life considerably.

I would definitely suggest annealing every sizing with your current dies, but even this might not be enough to fix the issue.

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Thanks for the info. Might look at new die.

Quote:

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Originally Posted by dale

Thanks for the info. Might look at new die.

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Just change bushing size

Sorry to hear about your brass.

For comparison, here are some neck splits on my Norma brass.
These were 2 failures from 134 cases I reloaded this week.
Its a 7mm08 using Redding FL dies and the cases have been reloaded about fifteen times.
I havent measured the neck dia before and after. I use an expanded ball.

Attachment 205001

Quote:

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Originally Posted by Bagheera

Sorry to hear about your brass.

For comparison, here are some neck splits on my Norma brass.
These were 2 failures from 134 cases I reloaded this week.
Its a 7mm08 using Redding FL dies and the cases have been reloaded about fifteen times.
I havent measured the neck dia before and after. I use an expanded ball.

Attachment 205001

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15 times. Do you anneal every time?

15 times!!!! have you used a feeler guage????

I've had them annealed once.
Thanks heaps @10Ring he did half of them.

What's a feeler gauge ? what are you looking for ?
I think that's what I used to use on spark plugs.

I feel fortunate I haven't had to go down many rabbit holes.
Nor checked my own spark plugs for a while.

Ok firstly, is that a dent?

Attachment 205086

I've used three different brands of brass in my 7mm rem mag and had split necks with Federal and Winchester so far.

The Winchester necks split if you look at them funny :XD: I've actually had a few go on their first firing out the box, factory ammo! I had about 80 cases, different batches with half of it given very generously to me by my brother who does not reload. This brass has been loaded 8 or 9 times and is sitting waiting for me to get it annealed in an emergency when I can't get brass, primer pockets have held up well and I think I've got about 60 left and if I hadn't loaded so hot early on I would have quite a few more. The federal stuff, same again, different batches, some bought off trademe as once fired, and its been good too, I think only half a dozen lost to split necks with a couple to loose primer pockets, my fault loading too hot again :psychotic:

I recently switched to Norma and I've used the same set of RCBS dies the whole time I've owned the rifle and only just now been concerned about how much they are working the brass. Fired, the neck measures 0.315, sized without the expander its back at 0.300. expanded with the standard expander its at 0.310 and loaded it's at 0.312. I've only got one firing on this stuff, same batch bought brand new, very fancy :ORLY:

From what you guys are saying that's a lot of work so for Winchester and federal to stand up to that much work for several firings and have a pretty acceptable failure rate I would say you've got either a brass or chamber problem.

Quote:

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Originally Posted by dale

Thanks for the info. Might look at new die.

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If only

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Originally Posted by Kelton

If only

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Don’t be like that :ORLY: I also managed to pick up 100 adg brass to chase me further down this rabbit hole. And have been looking at a amp annealer. Fuck my life !