The internal diameter of the clean primer pocket is between
4.40mm and 4.42mm.
The one with the ring is
Between 4.35 mm and 4.37mm
That clinches it then.
In that case (scuse the pun) it is not the remains of the primer cup that is showing as silver inside the pocket. I would expect the primer wall thickness to be around 0.5mm and so the diameter difference inside and out would be almost 1.0mm if there was any bits of the primer wall left in there.
As others have said you should be good to just chamfer out with a countersink bit those cases which have the ring crimp. If you match the chamfer on the other cases you will have an easy guide for the new primer.
Still puzzled by your "silver ring" description though...
Alan
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