The case in the photo has been fired 12 times.  It has also been FL sized.  After it's 11th firing and sizing, it fit flush in the gauge.  But now, after its 12th firing and sizing, it will not fit flush in the case gauge.

My inclination it to simply retire the case as, after 12 firings, it owes me nothing and my guess would be that if the case head is stretching enough to not fit in the gauge, the primer pocket isn't long for this world although no cases in the same group have been retired due to loose primer pockets...  One other piece of information - about 60% to 70% of the cases in the same group have been retired due to failing the ICHS/paperclip test.

Could some of you more experienced reloaders give me some insight as to what you would do with the case or just comment.  The case otherwise seems to be OK.  I test seated a primer and while the primer pocket wasn't exactly tight, it wasn't ridiculously loose either.

I read the title and came in here ready to type "lower your sizing die", but I'm assuming other cases sized at the same time fit the gauge? If so, that is odd and a new one on me.

I'd probably lower the die and see if it will size just for shits and giggles, but yeah, I'd say it's scrap if it's not sizing in a properly set up die.

Flip the case over and find out if the rim will fit the guage.

Drop in gages are one step better than nothing, a very small step.

If all the other brass gaged fine then like the previous poster suggested, you have a burr or imperfection that isn't allowing the rim to enter the gage.

I use Mo DeFina's gages or Hornady's Lock-N-Load system. They give me readings in .001" increments which allows me to fine tune my dies precisely.

Never thought of that!...  flipped the case over and the rim fits in the gauge with ease!

BTW - the case was sized in a match grade Hornady die.  The die contacts the shell holder to produce an obviously noticible cam-over.

A drop in gauge isn't the only thing I use!...  I also measure/check headspace with 2 different devices as well as case trim-to length (2.005"), COAL, CBTO, neck OD on sized cases, and occasionally concentricity.

it really is time for new brass

Could it be that particular case didn't have lube in the neck during resizing and the shoulder got pulled up?  Only other thing I got you ruled out with turning the case over and it fit.  Is there a burr anywhere on the case?

**edit
I wouldn't think the head is very stretched looking at how sharp the head stamp is.  When I get to 10 or more firings, the head stamp is getting hard to read.

Get rid of the case

You more than got your use out if it.

I have plenty of new cases (as well as about 150 once fired Federal cases just like the one under discussion) waiting in the wings to be put into service.  The purpose for this thread is to help me (and maybe others) understand a little more about the phenomenon.  

Yeah, I said that in my OP...  

Perhaps after so many firings, tired brass has lost enough elasticity ("springback" or whatever the proper term is) to cause the problem.

Impossible!  FC cases are soft and are not suitable for reloading..

I jest.  You've got some good use out of that case.

I've personally never had a problem with FC cases in 5.56 or .308.  I've got coffee cans of FC .308 from my days as a LEO.  All from FGMM ammo.

Edit - come to think of it I have had the odd case or two over the years that just wouldn't size.  I just tossed them.  Can't recall the headstamp.

This

As suggested above, flip it over and see if the case head has expanded too much to ever fit the gage.

Inspect for small burrs that might prevent it from entering gage and remove with a fine file.

If case head fits and the burrs are gone, relube the case, readjust the die (to a smaller dimension) and resize.

Some brass, as it ages and hardens, will require a different die setting to get to the proper dimensions.  It will likely happen to all the other cases in the batch, too.

Federal brass + 12 firings = Better test for incipient case head separation (paper clip test).

I have heard all the stories about how soft Federal brass is.  These case I bought as a case (200 rounds - 20x10) of Federal GMM168s.  These were the first things that I shot from my rifles - for break-in, sight-in, and some practice...  So I saved the cases to reload to help me work out the kinks before pulling out my "good" cases (I have 3 boxes of new Lapua 308 brass) for "serious" reloading...  Because of what I had heard, I didn't have very high expectations regarding working life of these cases.  I was pleasantly surprised when I got to 10 firings before I lost my first case of the group.  I am now at 12 firings on the group and have lost 75% of the cases mostly to ICHS and a few to "fat" case head (like the one in the photo above).  I have never annealed a case and I have had not 1 cracked neck in the group.  Admittedly, I am careful not to over work my necks - I use a "match grade" FL sizing die with neck bushings,  I resize in 2 operations, and I never use an expander.  I plan to work on my technique a little more to be more careful with my headspace and maybe I can decrease the loss to ICHS for the next batch!...

As far as I am concerned, Federal "FC  308 WIN" brass (from FGMM) is GTG for reloading.  It has shown good case life and pretty good consistency.

Cheers!... and thanx again!

- R -

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I have been paperclip testing these cases every reloading cycle since I found a case from this group with ICHS after 10 firings.  I posted a PSA thread HERE at the time.

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Gentlemen;

I thank you all for your contributions.  The case will be enjoying its new home in my scrap brass bucket...

Best,

- Reorx -

++1

P.S.  I was taught to do the "Paper Clip Test" when I started reloading.

Everyone new to reloading should be taught this.

It's probably too late but you really should measure the headspace and case web dimensions and compare those to its brethren to see what's different.  That's really the only way to tell for sure why it's not gauging.

Serious non-troll question - What lube are you using?  If the case headspace were out of the norm it could be lube or a lazy crank of the handle when sizing that case.