"When people ask me what to buy, I tell them pick the largest caliber you shoot well and practice regularly, till you can shoot no larger than 12" groups down to 25 yds, then you have the "best" caliber for you."
States Rightist, Sounds like solid advice, but are there actually shooters who can shoot a .45ACP or a .40S&W as well or better than a 9mm? Thanks, and thanks Gorenut.
That's kinda of a loaded question with several answers, but I'll give you my thoughts.
The .45 1911 is the basis for modern shooting competitions, note I said modern, revolver contests were the beginnings of it. There were many years the .45 1911 was considered the most accurate gun made. Many believe it still is.
If you noted any bias in my thoughts, it was as based on what Jim noted, LE and the military went to 9mm so women could handle the sidearm. I have very distinct feelings on the value of personnel you have to make exceptions for, but that's another debate. As far as the 9mm goes, it is a very accurate round and a good CCW choice. When you look at LE and military findings, due to it's lower recoil, it is the round members of each shoot the most accurately. This is a shooter comfort phenomenon, not a ballistics thing. You will note LE and the MCS are now gravitating back toward larger calibers.
I personally despise the .40 because I do not like the different way it's recoil is experienced and I see it as a compromise round. This is purely personal bias on my part, it is a fine round, I'm just stubborn some times. The 40's street results are excellent.
So to answer your question, you need to ask which are accurate enough, by that I mean if one shoots 1/2" smaller groups out of a vice, does that make it a better CCW weapon, no it does not, all are accurate enough for that. If you were a comp shooter, then it would matter.
If you are looking for the caliber more people shoot well, buy the 9mm. If you can rent all of them, buy the one you shot the best. Your 9mm compromise is lesser barrier penetration, but as a CCW, that's rarely an issue.
Recoil does not bother me and I shoot big bores well, I carry CCW a 1076, M29 or 645 a majority of the time with either a 642 or CS9 BUG. I feel more comfortable and better armed with a larger round, but again, that's personal opinion, not something there is absolute concrete data to support.
Hope that helps......
One other thought, 9mm is cheaper to own and shoot, if money's an issue, as Jim said, practice time means more than caliber above the .38spl level.