Well, he brought it up! And yes the following is just my opinion for whatever it is or is not worth. Its good to have discussions that may help others or even the OP.
And I agree with the test it, not measure it. Ergo, can you slip a fired case back into the chamber? That is the real test, any other device has some degree or error and we are not talking much.
It certainly sounds like excessive set back of the shoulder.
When I measure a fired case and size it with a set back, I test the case in the gun again. I do a minimum and expect some cases not to let the bolt close right (note, old Sako's have a very tight bolt so you need to do it on an empty chamber to know how much resistance to closing there is)
I have done thousands of cases and since I did the minimum set back, I wear out the primer pockets before a case head crack. 8 firings with being careful on set back should get you at least 20 firings.