If you have a fired case from that gun measure the outside neck diameter, then measure the neck diameter of the Hornady case. Hornady 11 edition shows a neck diameter of .275, your fired case should be within 3-4 thousands of that, if not 5-6. If that Hornady case gauge is close to that .275 number it might not be opening up enough to get a proper measurement and putting marks on the bullet as well. If any doubts take the same marker to the neck of the Hornady case.
Just measured the fired case and the OD is .275”. Then measured the Hornady modified case and OD is .273”. The modified case slides into the chamber easily and a bullet moves freely in and out of the case.
