Signs of case head separation once fired brass

[Kudu101]

Hello, I'm hoping someone can help me with a question I have.

I full length sized a batch of once fired 243 factory federal ammo and about half now have this light coloured ring around the base. If this a sign of case head separation in the future?

what could have caused this to happen?

Should i discard these?



Many Thanks

 

[Alantoo]

At the risk of displaying my beginners ignorance they look fine to me. It is just the pressure mark from the full length resizing die as far as I can tell.

Either that, or both of us are doomed, because mine have that as well.

Hopefully some one with more experience will confirm this.

What lubrication did you use? Did they stick in the die any more than usual?

Do you have someone handy who can give the actual cases a once over?

Alan

 

[takbok]

Hi, those are just marks from the FL sizing die. You'll be fine.

You may be able to reduce these marks if you're able to adjust the die out a bit more whilst still allowing easy chambering.

 

[Conure]

Fairly normal now either your chamber is on the larger side of the normal spec or those factory cases are on the smaller side of the normal spec. If you can try a few factory rounds of anther make and then size those cases and see if they look the same.

One way to check for case head seperation is to make a small hook from a straightened out paper clip then use the small hook to feel insde the case for a ring just above the bottom inside the case. Another wold be of course to sacrifice a case by cutting it in two or just a window out of the wall by this ring mark.

 

[Muir]

Don't saw anything on this batch. Those are normal sizing marks. ~Muir

 

[bewsher500]

Hello, I'm hoping someone can help me with a question I have.

I full length sized a batch of once fired 243 factory federal ammo and about half now have this light coloured ring around the base. If this a sign of case head separation in the future?

what could have caused this to happen?

Should i discard these?

View attachment 69137

Many Thanks

what you are actually seeing is an absence of sizing below the web
the "light coloured ring" shows none of the brightening marks that the rest of the case shows

if you want to see indication of case head separation look at them immediately after firing and before sizing

 

[finnbear270]

what you are actually seeing is an absence of sizing below the web
the "light coloured ring" shows none of the brightening marks that the rest of the case shows

if you want to see indication of case head separation look at them immediately after firing and before sizing

Good pics Ed.

 

[Kudu101]

Thanks for putting my mind at rest everyone. I was using lee reloading lube and as its my first time resizing brass im not sure if it was sticking more than usual!

I do have some sako brass so il see if they resize differently.

In comparison to bewshers photos these are just shiny rings no indent whatsoever.

Thanks again.

 

[daryl8837]

use a neck sizer die (NSD) instead of a full length sizer (FLS). The FLS weakens the case every time used the NSD only sizes the neck and because of this the case body expands when fired and it will fit your chamber better which increases accuracy. The FLS die over time will make your case brittle and you will eventually get a cracked neck on firing. Only FLS every 10 times fired. If you want your brass to last nearly forever you need to anneal the neck. Heat the neck with blow torch for 2 seconds only! do not let it glow red! that weakens the case. Doing this keeps the neck supple and will never crack.

Thanks
very experienced reloader

 

[Muir]

use a neck sizer die (NSD) instead of a full length sizer (FLS). The FLS weakens the case every time used the NSD only sizes the neck and because of this the case body expands when fired and it will fit your chamber better which increases accuracy. The FLS die over time will make your case brittle and you will eventually get a cracked neck on firing. Only FLS every 10 times fired. If you want your brass to last nearly forever you need to anneal the neck. Heat the neck with blow torch for 2 seconds only! do not let it glow red! that weakens the case. Doing this keeps the neck supple and will never crack.

Thanks
very experienced reloader

How does FL resizing make the neck more brittle than neck sizing alone? I full length resize everything, including my long range ammo. (good enough for Lapua's Match ammo? good enough for mine!) I am with you on annealing. Very important as a measure to extend case life. On that subject, and FWIW, this is a quote from Lyman's latest reloading manual:

"Reloaders sometimes opt for neck sizing based on expecting increased case life. With normal chambers, neck sizing versus full length resizing offers little case life advantage. Thus, Lyman suggests full length resizing as the norm, especially for hunting loads where smooth feeding, chambering, and extraction are important."

I've found this to be true.~Muir

 

[Ted47]

use a neck sizer die (NSD) instead of a full length sizer (FLS). The FLS weakens the case every time used the NSD only sizes the neck and because of this the case body expands when fired and it will fit your chamber better which increases accuracy. The FLS die over time will make your case brittle and you will eventually get a cracked neck on firing. Only FLS every 10 times fired. If you want your brass to last nearly forever you need to anneal the neck. Heat the neck with blow torch for 2 seconds only! do not let it glow red! that weakens the case. Doing this keeps the neck supple and will never crack.

Thanks
very experienced reloader

you can use your fl die to re size the neck , you will have to fl size your cases when they need to be done(when the bolt starts to get get tight when closing )as different cases can stretch at different amounts.
every blowtorch differs, even the gas used will heat at a different temperature, use tempilaq to get the correct temperature timing.

 

[bewsher500]

How does FL resizing make the neck more brittle than neck sizing alone?

A standard FL die with expander ball has to work the brass twice as much as a collet neck die. That must have some effect

Once when compressed into the die, again when it is expanded

Collet Neck sizer just once onto mandrel

 

[deeangeo]

use a neck sizer die (NSD) instead of a full length sizer (FLS). The FLS weakens the case every time used the NSD only sizes the neck and because of this the case body expands when fired and it will fit your chamber better which increases accuracy. The FLS die over time will make your case brittle and you will eventually get a cracked neck on firing. Only FLS every 10 times fired. If you want your brass to last nearly forever you need to anneal the neck. Heat the neck with blow torch for 2 seconds only! do not let it glow red! that weakens the case. Doing this keeps the neck supple and will never crack.

Thanks
very experienced reloader

Two seconds is exceptionally brief to anneal correctly, but then I don't know what cases you anneal with that short a time under a torch. As for neck sizing, it's a short term quick hit, especially if loading hunting rounds. For absolute reliability, full length resizing is certainly the way to go. And, if you full length resize to fired case headspace dimensions, as well as anneal, extended case life is assured.

Incidentally, referring back to the original post, I absolutely agree with others who identified the marks as pressure witness marks from the die.

 

[bewsher500]

I predominantly shoot to hunt
i neck Sze everything without issue
i have 10+ fired brass that has not been annealed in some rounds
not to be over looked

 

[deeangeo]

I predominantly shoot to hunt
i neck Sze everything without issue
i have 10+ fired brass that has not been annealed in some rounds
not to be over looked

That's nice!

 

[Conure]

As I understand when annealing the metal has to reach the critical temperature for the grain structure to alter. If it does not reach this tempreture then you may as well not bother wasting the gas and time as you have done nothing but make them a little hot. Trying to remember back to school now but a web search will bring up the correct information I do not doubt.

 

[Cloudhopper]

As I understand when annealing the metal has to reach the critical temperature for the grain structure to alter. If it does not reach this tempreture then you may as well not bother wasting the gas and time as you have done nothing but make them a little hot. Trying to remember back to school now but a web search will bring up the correct information I do not doubt.

Sounds about right to me.

I can't see how anyone can anneal consistently without process control, i.e. it needs to be automated.

CH

 

[deeangeo]

Sounds about right to me.
I can't see how anyone can anneal consistently without process control, i.e. it needs to be automated.
CH

It's a simple enough process and can be done perfectly competently & satisfactorily without the need for automation. There's simply no need to over complicate.

 

[Muir]

A standard FL die with expander ball has to work the brass twice as much as a collet neck die. That must have some effect

Once when compressed into the die, again when it is expanded

Collet Neck sizer just once onto mandrel

I understand that but the poster didn't specify "collet die" , he said to simply neck size. I have a lot of neck sizing dies that aren't collet dies.~Muir

 

[Alantoo]

As I understand when annealing the metal has to reach the critical temperature for the grain structure to alter. If it does not reach this tempreture then you may as well not bother wasting the gas and time as you have done nothing but make them a little hot. Trying to remember back to school now but a web search will bring up the correct information I do not doubt.

Interestingly in an earlier thread it transpired that the use of the word annealing is a bit of a misnomer peculiar to reloaders.

What reloaders are calling annealing, metallurgists and metalworkers call stress relieving, don't be fooled like I was.

According to the Copper Development Association:-



Whether it actually makes any difference or problems if you do actually anneal, as long as it is consistent, I don't know.

I, in my ignorance of this misnomer, annealed some cases in the metalworker sense and fortunately the resulting rounds grouped as well, if not better, than some HPS target rounds in new Lapua cases...

Given that the surface colour change is so subtle at the stress relieving temperature, and can be hugely affected by the ambient light and degree of tarnish on the brass, using tempilac paint on the inside of the case mouth seems favourite.

A friend is exploring the system of dipping the case neck and shoulder into molten lead, which is around the stress relieving temp for cartridge brass...a layer of graphite on the lead surface to prevent the lead from adhering...

Alan