However you manually measured that cylinder the first time may be 8mm off in Y compared to the auto measured ones. I am not entirely sure. Can you post your code with a code tag if possible? You also didn't do any sample hits on Cylinder C, so it just went back to the exact place you measured it the first time manually without touching off the face, so the Y value will be pretty close to the first run, since nothing is controlling the Y axis except your manual probe placement.