According to FBI statistics, the most effective round is a 357 mag.
I might take issue. I have a booze addled brain, but I remember when the whole 9mm thingee started back in the ‘90s, the FBI did a really big study. And they concluded that if it didn’t start with a .4xx, it wasn’t a good deal.
Please don’t ask me for the name of the study. The NRA published it in the American Rifleman.
Me personally, I like the .357. Especially with my own loads.
Versatile, wicked and effective. I shot IPSIC with it a few times in a model 19. The buggers gave me a handy cap because I was using a revolver. They all had autos.
I shrugged off the handicap and beat some of their best times.
Fun was had by all.