The Wilson case gages are great tools, but when I run into troubles or I\’m loading for a major match, the barrel from the gun I\’ll be using becomes my case gage. ALMOST foolproof! My 9mm 1911 isn\’t real fussy, but my CZ Shadow 2 is.
Understand that putting a hollow point or a flat nose on a bullet changes its mass distribution. I find it useful to measure the length of the bullets I\’m using as part of my loading strategy. E.g., a 124 HP will be longer than a 124 RN, so if you don\’t change the seating depth (thus OAL), the HP will be seated deeper into the case and will normally result in higher pressures and velocities.