our blank sheet measures the exposed end and nothing else

We have the blanks, but they went back into one tote. I cannot honestly assign the old readings to individual pieces. We can start a new identified set.

Start again with identified blanks. Measure overall length and inspect the end used for seating; record exposed length against the same identity using the setter's agreed method.

Have the setter keep the loading method consistent for that comparison. A second person changing the method halfway through would leave you with another sheet that is hard to interpret.

And keep the actual blanks this time.

The new sheet shows two overall-length groups. With our setter's check, the longer blanks also have the longer exposed length. One short blank remains an exception; its seating end has a raised edge. That one is set aside for inspection.

Do not merge the raised-edge example with the length variation. What did quality find on that end?

Quality confirmed a burr on the end of that blank and rejected it from the trial samples. The identified remaining blanks reconcile with their overall lengths. That explains this sample set; the planned automatic loading still needs its own assessed trial.