I appreciate what ContinentalOP has to say above. I'm about exactly on the same page with him in this matter. For me personally, my answer to this question has changed over the years, primarily because if the advancements in handgun ammunition that have been made.

If all we could use in our handguns was lead round nose bullets or FMJ hardball, I'll take the .45 every time all day long. I happen to be able to fire this caliber about as well as I can any other the smaller calibers. Some folks cannot do that. Not a problem these days!! I am perfectly comfortable carrying anything from 9MM/.38 caliber up to the .45's. My needs these days is primarily personal protection. Any of these rounds with a good premium bullet will do the job IF I do my job correctly. NONE of them will work if I don't do my job! We've all read that emergency room doctors and pathologists who do autopsies can rarely tell the difference in that damage that any of these calibers have done. If they don't find the bullet in the body, or have some external evidence to tell them, all they really can say is that a bullet did this!

We enjoy discussing what's "best", and that's OK. EAch of us must make our own choices and live or die by them. What's best is what's best for ME! That pertains to both ammunition and the firearm that shoots it. What gun can I shoot the best? What ammo works all the time, every time in that gun? And which combination of the two allows me to fire multiple controlled shots and land those bullets where they need to land to have the maxiumum effect to get the job done? That might be the same combination for you and for me and for maybe the large majority of others looking for the same thing. Or what is best for me might be best for a very few others. You nor I can decide what's best for ourselves unless we examine and test and try (with a very open mind!) the available choices. Generally, we will find that we have several choices of both handguns and ammunition that will be very satisfactory choices. So then we can choose among them and pick what WE (I) like the best. Then we can go practice with it to make sure we can use our choices to their maximum effectiveness and do so under high stress and pretty much subconciously. Then we can hope and pray that we are never in that circumstance and have to use our choices for extremely serious purposes.

C'mon guys. Most of this beyond a certain point is a "mine is bigger than yours" discussion. So what? That's always the case when comparing, right, except for the opposite outcome after measurements. I like to learn about things as much as I can. What I really like to study are outcomes of actual shootings. But even then, the multitude of variables are so great that it's difficult to compare one shooting to any other. All we can do is do our best and hope for the best outcome.

Since practice with whatever you choose is important, and because there are so many good choices of well made and dependable handguns out there to fit almost any hand size, I say it's likely that the best choice among all of what's available is to find a good quality 9MM striker fired semi auto that's reasonably priced and then buy a 1000 rounds of good quality practice ammo and go shoot! 9MM has the benefit of being the cheapest priced ammo on the market today (with some of the usual exceptions ... but across the board everywhere). Get something you can use well and enjoy using that fits you and your budget and go shoot it. You don't have to shoot a thousand rounds a month, unless you want to do so, of course. But sadly, most of us go buy ourselves a handgun and a couple boxes of ammo, maybe shoot it a few times, and call it good. A handgun (or any gun!) ain't a magic pill. If you can't be very familiar with it, know that it'll go bang every time, and that you can hit the target with it, you'd be better off with a sack full of nice smooth easy throwing river rocks. They throw easier than does any hangun!!

Shoot what you can shoot the best with the most confidence, and know that you will have done the best you can do and the ammo will have done it's job too. Anything can and does happen when somebody gets shot. Sometimes it works well and sometimes it does NOT! We just need to have the mindset that we are going to protect ourselves with whatever we have or can lay hands on and we ain't gonna quit as long as we can lift a hand. That's the only chance we have to survive!!

Sorry ... got on my soapbox. Hope you find something of interest to think about here. Like I said, just my own thoughts presented to all for what ever, if anything, they might be worth!! Thanks for reading this far if you did!

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So long ... Ken