Is this a headspace issue?

[JimTom]

G’day Gents

Fired a few rounds out of a mates rifle the other day at the range and noticed this band around the bottom of the case, which coincides with a slight deformity commensurate with what I would think is impending case separation. Rifle is quite old circa 35years, and exhibits all the signs of being used . Brass is of an unknown age and number of firings.
Headspace issue perhaps?
Over to the brains trust for discussion.

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[JimTom]

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[Strikey]

They're the marks from the FLS die and can probably use a bit more lube when sizing.

[Blr243]

I use a sharpened end of a paper clip bent at 90 degrees to insert into the case and feel for a potential failure ... haven’t Had an issue for probably 15 plus years

[bladeracer]

G’day Gents

Fired a few rounds out of a mates rifle the other day at the range and noticed this band around the bottom of the case, which coincides with a slight deformity commensurate with what I would think is impending case separation. Rifle is quite old circa 35years, and exhibits all the signs of being used . Brass is of an unknown age and number of firings.
Headspace issue perhaps?
Over to the brains trust for discussion.

62C7C980-6DF7-47F5-843D-BF5D1401508B.jpeg

That looks like the bottom of the FLS die, not separation.
If the brass is fire-formed to the chamber headspace won't matter, as long as you are not sizing it right back to OEM spec.

[in2anity]

What’s the action, JT?

[deye243]

That is caused by a sloppy factory chamber that is the intersection of the case wall and the web part of the case nothing to worry about but if you keep full length sizing you're going to run into trouble .

[marksman]

its a sloppy sammi chamber
the chamber is bigger in diameter than the case is
the problem he will have is that when using cases that are thicker on one side than the other, the thinner side will have more bulge making the case offset in the chamber so the bullet will not be in line with the bore causing inaccuracy from shot to shot
your mate would do well to use some PPU brass as its made a tiny bit larger in diameter and to check for lopsidedness in the case after firing in his chamber then only neck sizing the case to keep consistency
or FLSing and reloading with the bullet jammed so the bullet starts off in line with the bore

this is more common in older rifle chambers than people realise but is not dangerous just inconsistent

[LawrenceA]

I use a sharpened end of a paper clip bent at 90 degrees to insert into the case and feel for a potential failure ... haven’t Had an issue for probably 15 plus years

What he said.

Or cut a case in half and have a look.
If it is imminent head separation, then it can be a variety of things.
Head separation is caused as the brass walls on the case stretch and grip the chamber walls and as pressure rises the head of the case is pushed back stretching the case and thinning the brass at that point.

So basically it is caused by case stretch. This in turn can be accelerated by pressure, the type of action (rear lockers stretch more than front lockers), headspace and case to chamber fit.
That is all I can think of.

Hope this helps

[JimTom]

G’day Gents

Fired a few rounds out of a mates rifle the other day at the range and noticed this band around the bottom of the case, which coincides with a slight deformity commensurate with what I would think is impending case separation. Rifle is quite old circa 35years, and exhibits all the signs of being used . Brass is of an unknown age and number of firings.
Headspace issue perhaps?
Over to the brains trust for discussion.

62C7C980-6DF7-47F5-843D-BF5D1401508B.jpeg

That looks like the bottom of the FLS die, not separation.
If the brass is fire-formed to the chamber headspace won't matter, as long as you are not sizing it right back to OEM spec.

I had FLS these cases so it was the first firing since doing so mate.

[JimTom]

What’s the action, JT?

Mate it is a Parker Hale so a Mauser 98 action as I understand it.

[JimTom]

That is caused by a sloppy factory chamber that is the intersection of the case wall and the web part of the case nothing to worry about but if you keep full length sizing you're going to run into trouble .

Thanks for that mate. I only FLS when it is needed however I do t know the history of the brass.

[JimTom]

Thank you everyone for your input. Sincerely appreciated.

[animalpest]

Old Parker Hale rifles typically had sloppy chambers. My old 30/06 looked the same until it was rebarrelled.

As has been said, check the inside of the case with bent wire.

[in2anity]

It’s where the chamber ends, making way for the bolt. Very common in old service rifles. Eventually the case will fail with head separation, you should aim to chuck em before that point. Still, case head separation on the mound is common - there are tools designed for extracting a separated case. I haven’t had too much personal experience behind old mausers, but fwiw 303s also exhibit this strongly. The case starts to bulge at that fail line after many reloads, especially if you are FLSing all the time. That’s why neck sizing is very popular among service rifle shooters.

Moral of the story, if you want to squeeze the most out of your brass, avoid FLSing as much as you can. Do the paper clip trick to determine the condition of your brass.

[marksman]

funny enough l have a barrel off a parker hale M98 so l can show you guys that the case fits up to the extractor rim on a mauser 98
remingtons dont they have +/ .150" of the case head out of the chamber, that's why they have to have the 3 rings of steel they glorify in advertising
mauser 98 dont need the three rings of steel

for a case head separation to happen the case brass moves forward when fired until it thins out enough to snap off at the web, brass only moves one way when fired
in the case of this one the cases are bulged from a larger sammi spec chamber and until the brass has moved forward it will be safe to use
this is a very common thing in factory sammi spec chambers

and if you have a good look at the 3rd photo JT has posted up you will see it looks to be bulged more on the bottom of the case than the top of where the bulge is happening that will cause the case to be offset in the chamber

[pomemax]

Do you have any rounds that were not fired and were the marks on them . to me First impression was FLD not caming over

[in2anity]

Typical aging 303 brass.

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[JimTom]

Do you have any rounds that were not fired and were the marks on them . to me First impression was FLD not caming over

Mate I fired some brand new factory loads this arvo and the cases are exactly the same, so not related to FLS. At least I have ruled that out so one step closer.

[GojiraSteve]

Do you have any rounds that were not fired and were the marks on them . to me First impression was FLD not caming over

Mate I fired some brand new factory loads this arvo and the cases are exactly the same, so not related to FLS. At least I have ruled that out so one step closer.

I have seen it almost universally on unfired S&B 100gn .243 ammo, and here and there on other stuff. Best guess so far is that the brass is annealed to that line as part of the manufacturing process (and then presumably re-tempered). But neither me, nor the bloke who made that guess are any kind of expert.

Pre-firing it seems to be more apparent/visible on rounds that have started to tarnish a bit in the box. But tarnished or shiny its really obvious once they've gone bang.

[JimTom]

Worthy of consideration for sure however I have recommended that the rifle be taken to a gunsmith for a definitive answer.

[marksman]

Worthy of consideration for sure however I have recommended that the rifle be taken to a gunsmith for a definitive answer.

its a smart idea to be sure and get a definitive answer

l just saw this photo which l will attach that shows the bulge that l am talking about, with a yellow line pointing to and the mark of a head case separation ring forming with a red arrow pointing at it showing the headcase separation is very apparent from the inside of the case but not the outside because the outside of the case will form to the chamber , l thought it might add to this thread to show it

[JimTom]

Thanks for that mate. Pretty certain that is what I am dealing with too.

[LawrenceA]

It just dawned on me that this may be a 6.5x55.
If it is then it is worth knowing that many military chambers are on the large side of tolerance but more specifically the 6.5x55 has a .476 rim versus the more common .473 you see in the 30-06 family.
I have noted that some ammunition seem to be made to suit a .473 head diameter whereas Norma is .476.

[JimTom]

It is a Parker Hale .270 Win mate.

[cirles]

To add another visual example for impending head separation this is a recent video by 'f-class john' which showed a distinct line forming (almost as if scribbed) on the case. The image that marksman included shows a couple of lines though one seeming to be off kilter. Assuming f-class john rifle has tighter, more supportive chamber dimensions so the bulge not showing.

https://www.youtube.com/watch?v=mPkaqimrohs