Stress Rings on full resized brass normal?

[BeagleBoy360]

So I've been just neck sizing all the brass ive already shot out of my rifle, and now just bought once fired brass from a guy on CGN.
I went to full length resizing, and the first 5 i've resized now have a ring on the base, I think this is normal, just want to double check before doing the rest and possibly messing them up.

It is a RCBS die, that i screwed down, and then turned around 2/8s extra turn to take out all the play.

Here is a photo.
Most of the rings are between 75% and 100% around the circumference of the brass.

 

[LUTNIT]

A regular sign of case expansion upon firing. Possibly a sign of case head separation but unlikely most of the time.

 

[BeagleBoy360]

These rings are not on the case before resizing, these rings are made by full length resizing.

A regular sign of case expansion upon firing. Possibly a sign of case head separation but unlikely most of the time.

 

[sdlonyer]

Would the 'extra' turns not prevent the case from being fully sized? Back it out 3 turns and see if the problem persists.

 

[LUTNIT]

Oh, my bad, I see them a lot on once fired brass before resizing.

If they don't show up until after sizing it is most likely just the point where the die stopped resizing the case. The case head is much thicker and shouldn't expand and thus shouldn't need resizing so the die doesn't go down all the way.

Either way they aren't a sign of anything bad unless there is obvious bulging around that area after firing.

 

[bigedp51]

Your neck sized cases expanded in the same area, it is where the brass is thin enough for the chamber pressure to force it outward to meet the chamber walls, meaning *normal case expansion.

Now the next time you shoot it try backing off on the FL die for minimum shoulder bump, on a bolt action .001 to .002 shoulder bump and on a semiautomatic .003 to .006 shoulder bump.

Over resizing your cases shortens their useful lifespan and causes case head separations.

NOTE: The .308 case below were fired in a new Savage rifle but the author did not state the rifles headspace setting or how far the fired cases had there shoulder pushed back. Meaning we don't know how much the cases were over resized or shoulder bump.





*Normal case expansion varies

Below, both these .303 factory loaded cartridges were fired in the same No.4 Enfield rifle.
The Prvi case has a larger base diameter and is .010 thicker in the base web area than the Greek HXP cases. Neither case stretched or thinned in the web area when fired, both are "normal" expansion. "YOU" have to learn what normal is for the brand of cases you are shooting at a given chamber pressure in YOUR rifle..

 

[*MALICE*]

They look like burnishing marks from the sizing die. I'm often overly paranoid about them too but when you put a case like that next to one that close to separating there is usually a quite obvious difference.

Use a paper clip with a hook on the end to feel the inside of the case for a groove.

 

[bigedp51]

They look like burnishing marks from the sizing die. I'm often overly paranoid about them too but when you put a case like that next to one that close to separating there is usually a quite obvious difference.

Use a paper clip with a hook on the end to feel the inside of the case for a groove.

The RCBS Case Mastering Gauge has left the paper clip in the dark ages and gives you reading you can "SEE".

 

[*MALICE*]

Don't make me show you up. I'll have to post a pic of me measuring a case on the CMM at work

I (possibly mistakenly) assumed the OP did not have a dial indicator to gage his cases

 

[dirtytwo]

The RCBS Case Mastering Gauge has left the paper clip in the dark ages and gives you reading you can "SEE".

A case gauge like this is your best friend, especially when reloading for military rifles with generous chamber dimensions.