41 Magnum,,, the concept of buying a revolver in a caliber made for a semi-auto goes back to the days of LEO's being issued a semi over the traditional revolver. They wanted a B/U gun in the same caliber as their duty gun, and were allowed to choose whatever B/U gun they wanted. Due to being familiar with the tried & true, darn near infallible, familiar revolver,,, they wanted them.
At least,,, that's what I understood for many years.
I used to win a few bets with folks who argued with me saying that "There ain't no revolvers in 9mm!" I'd politely provide a Speed-Six in 9mm. AND,,, if they persisted in arguing the facts,,, I'd provide the factory paperwork.
Now,,, it's much more common.
Axe,,, that crimp jumping is a pure puzzle. I'm sure you have tried various types of 9mm,,, and such. I own a LC9 but it's still new. I haven't taken it out to shoot & see how it does. I was kinda wondering if I should. Now,,, I may have to,,, just to see what happens.