Case separation?

[Blr243]

I expect it to start near the base , in the inside . And be mostly obvious with useing a sharpened paper clip. But tonight in some second hand 4570 brass I just bought I have just finished sizing and flaring and priming 150 cases. I just noticed the last case has a ring around the outside of the case . It’s visually obvious and u can def feel the groove with a fingernail. Never before have I seen it more obvious on the outside of case and only about 15 mm from the case mouth. I won’t be useing it

[Blr243]

The remaining 149 cases are fine

[Blr243]

And I’m stoked that today I found 1000 of my favourite primers in stock

[Blr243]

The groove is as deep and obvious as if someone started to shorten it with a set of cutters that a plumber would use on copper pipe

[Blr243]

And I’m stoked that today I found 1000 of my favourite primers in stock

[Oldbloke]

IMO that's not case separation. It could be a manufacturering fault.

[boingk]

I've seen some odd, old cases with very heavy crimp lines that almost look like that. Perhaps thats the cause? I'm struggling to think of something else.

Same opinion though, get rid of it... and good score on the primers!

[pomemax]

I payed $96 for a 1 k of large rifle CCI . 3 days ago in Sydney where did you get them from BLr was heaps here and rifle powder but not pistol
would be interesting to see in the chamber that fired the case

[LawrenceA]

Looks like where the base of the bullet would sit.
Not case seperation

[Blr243]

Primers were at QGE ... only one box of 1000 was sitting on the shelf so I grabbed it. There was a couple of loose boxes of 100 sitting there too but unsure if they were small rifle or small pistol or large rifle or whatever ".......

[Bugman]

If the case manufacturer is identifiable, then maybe send a pic to them and see what they say. I would be curious enough to do that if possible.

[straightshooter]

Not separation and not a crimping groove sort of.
It's a fairly old case from an era when a cannelure was rolled into the case to prevent bullets without a cannelure being driven deeper into the case under recoil in a tubular magazine thus risking excessive pressures.

[LawrenceA]

Not separation and not a crimping groove sort of.
It's a fairly old case from an era when a cannelure was rolled into the case to prevent bullets without a cannelure being driven deeper into the case under recoil in a tubular magazine thus risking excessive pressures.

This is what I was trying to say.
The groove is quite common on older cartridges of the hyphenated variety

[Blr243]

Mystery solved. Thanks. On closer inspection Some of the others cases have Feint Marks same spot but not weakening the case ... I shall observe and monitor closely anyway over the course of time

[Bugman]

The truth is revealed. Good stuff.