"Cdoc42,
Yes, you can measure the bulge over the bullet. Do it in two or three places after seating but before crimping, and then again after crimping to see what has changed."
Yep, I did it today, buried in my reloading workshop by Covid-19 boredom. Pre-seat case size, 0.357". Post seat, where the bottom of the bullet appears to be, 0.359." I suspect a larger reading would be commensurate with the inability to chamber the round.
It was really funny, actually. I had resized 50 cases of .45 Colt and began flaring with a setting I knew to be effective. One was particularly difficult, but not impossible. It happened to be a .454 Casull that had mixed in with the.45's. I wish I knew how to show you the picture. It looked like a feakin' mushroom.