I’m really fond of the .45 ACP. I generally carry one for self defense in various configurations. My wife says I accessorize.
There are of course different weights of projectiles from 185 to 230 grains. In that respect which is best for stopping a threat? The lighter grains feel like they recoil less, but is it the heavier bullet that does the trick or the diameter that causes the larger permanent wound channel?
I absolutely believe that accuracy is the best way to stop an attack and that caliber is probably not relevant. So is bullet weight relevant?
I, too, am really fond of the .45 ACP. I carried one for decades and to this day keep one in the rotation, mood, or environment in which I plan to interact (you know - different tool for different job sort of thing). Anyway, in an effort to answer your question: the definition of "best" for anything is relevant and, as wonderfully demonstrated earlier in this thread by
@Model 52 
, can be achieved in a variety of way and means. I am not a fan of +P anything. Not slurring, just not my thing and an entirely different rabbit hole to go down. Ammunition technology has come a long way from the days of old. However, I would not want to be shot with
ANYTHING from a JHP to a FMJ or even a .177 BB for that matter. They ALL will minimally leave a mark or a hole - some worse and/or bigger than others. However, IMHO, caliber is indeed relevant. A moped
will pull a car but a F-250 sure does the job better and a whole lot easier. Yes, accuracy is of utmost importance in neutralizing a threat. A well placed shot with a .22 will do the trick. However, going from zero to ten in a split-second and in the ensuing high-stress environment of a real, life or death gunfight with you and your family's lives at stake, are you willing to bet your life and the lives of the people you are protecting that you can put a round twixt the eyes of an erratic, meth-fueled, moving target and stop the fight with one shot? I'm a fair shot but I can't say with any amount of certainty that I could
consistently pull that off. Again, IMHO, I feel that a larger caliber gives you a little more "margin of error" with regards for shot placement and is therefore relevant. I can, and indeed do, recommend the Federal Hydra-Shok 230 gr. JHP for defense. From the rooter to the tooter to the toenail, if you hit a threat
anywhere with one of those, they will have to be mighty committed to continue their ill-fated course of action if they are able to get back up. Regardless of the path you choose, having something is better than having nothing. The old saying "don't bring a knife to a gunfight"? A knife in a gunfight is better than a fist so... I hope all of the information provided in this thread helps you in some way, shape, or form. As far as your wife saying you accessorize? I tell mine that's like the pot calling the kettle black. She just rolls her eyes
