Search:

Yep, you ned to start using measurements and recording them as you go.

Do you still have factory ammo? Another source of measurement.

You've got to quantify the datum point measurement and if...

OK that's good, you need to do some measurements with your vernier to determine the difference.
Is the measurement to the datum on the cases you are attempting to size still longer than your good...

I'll ask the question again. Can you corfirm that the case in pic one definitely fits and pic 3 doesn't?
If you have a case that fits a few measurements will tell you what the problem ig. eg an...

If your trying to use brass not fired in your rifle as well as the datum point measurement it is useful to measure the base diameter 0.1 up from the base and compare.
I have second hand brass that...

Can we just go back to posting #6. Can you confirm that the first picture shows a case that fits your chamber?
And the third picture shows a case that doesn't?
If that is the case the last picture...