I did spend around five years in law enforcement, have been a firearms instructor for over twenty-five years, have about twenty years of concealed carry experience, taken a lot of training myself, and I'm an American citizen with the right to keep and bear arms who has learned a lot over the years about handguns, sometimes through the school or hard-knocks and out-right mistakes (don't ask me about my friend's Jennings 22 that literally broke apart in my hand while shooting it back in high school).
So what follows are some of my own thoughts and opinions for ya'll to consider that may be in line with many main-stream and big-name folks in the gun culture and some comes my experiences with teaching new shooters and helping many folks select handguns for many years.
1. Caliber
The gals and I usually carry a 9mm or a .38 Special/.357 Magnum. I own several .45 ACPs and love to shoot them, but their heavy, have far less capacity than 9mm and most things I've read indicate minimal statistical differences in "stopping power" or "rate of incapacitation" between 9mm, .40 S&W, and .45 ACP. With that in mind, I want to be able to pull the trigger and have the gun go "BANG" as many times as possible before having to reload. That's why I carry a 9mm. In any given size gun, it will hold more 9mm rounds than .40 S&W and .45 ACP. Recoil - on average - is more manageable for the gals and I, plus 9mm is common and cheaper so you'll likely practice more often... I know the gals and I do.
I have occasionally carried a .380 ACP as a back-up gun or just because of special circumstances and because it meets the first rule of gun-fighting's minimal criteria of "have a gun". There have been a couple of folks I've trained who were advanced in years and arthritis for whom I recommended a .22 long rifle or .22 Magnum, but those were special situations.
As far as revolvers go, there is really only one practical choice for caliber and that is the .38 Special/.357 Magnum calibers. The gals and I typically use .38 Special +P self-defense cartridges in our five-shot snubbies if we carry them even though they might be rated for .357 Magnum due to being able to control recoil a lot better. Again, .38 Special is common and cheap, so you'll likely practice more often. Again, the .22 long rifle or .22 Magnum are viable alternatives in special situations.
2. Size and Shootability
Let's talk about gun size and shootability as I believe they go hand-in-hand. Shootability is the capability YOU have to reliably and accurately shoot and operate a particular gun. Ideally you want a handgun that fits you and your hands, but often many folks go for a smaller handgun for concealability. Now I realize that folks with different body types, particularly smaller body types, may have trouble concealing larger handguns, but I've come to prefer carrying and concealing a full-size gun over the years for a number of reasons.
I find a full-size gun is easier to shoot more accurately, manipulate, and carry more rounds of "BANG". With a good IWB or OWB holster, I have no problem concealing a full-size handgun. Now that being said, there are times I do carry a compact or pocket-size handgun because I need it as a back-up to my main gun or I'm wearing an outfit (like working out at the fitness center) where carrying a full-size gun with a good, quality gun-belt is not an option.
Modern polymer pistols like the Ruger SR series, the S&W M&P series, Glocks, XD's and others offer a reasonable combination of full-size and lighter weight than the typical 1911's or the boat-anchor .45 ACPs like the S&W 4516 .45 ACP that was standard issue in the police department I worked for. Truthfully, the length of the grip of your gun is a far more troublesome aspect to carrying concealed than the length of the barrel. If Glock would make a gun with a Glock 17 barrel and a Glock 19 grip-size... it would make sense to me.
As far as revolvers go, the gals and I can shoot our full-size Ruger GP100 far better than our Ruger SP101 or Ruger LCR, but the SP101 and LCR are far more concealable. Snubby revolvers seem to be popular first concealed carry gun choices by many, but they are generally not easy to shoot accurately for new shooters in my experience as an instructor. I can reliably shoot a fairly tight, threat-stoppin' group at ten yards with my LCR, but I have to keep in practice to do so reliably.
The Ruger SP101 is probably the most over-engineered, over-built five-shot snubby available. The additional weight makes this the only .357 Magnum snubby I've shot that is actually truly controllable for me with full .357 magnum loads, although I typically carry .38 Special +P rounds in it. The problem is that it's a very heavy snubby to pack around all day compared with a lot of the lighter-weight offerings like the Ruger LCR or the Smith & Wesson Airweights, but it is lighter than the full-size GP100 or a Smith & Wesson 66 or 686. Is a lighter gun you'll carry regularly all day worth the loss in recoil control and accuracy many folks find with a full-size gun? That's something you'll have to consider for yourself.
Now small guns seem to be the hot ticket that last few years as more and more concealed carry license and permit holders have hoped to find a pocket-rocket that is easily concealed, sometime sacrificing shootablilty for concealability. Now I know that the first rule of a gun fight is to have a gun, but I've been finding more and more folks and students in my courses have gone out and purchased a snubby .38 or a pocketable .380 without actually firing the gun only to find that controlling recoil and maintaining accuracy can be quite the challenge. I can reliably shoot our Ruger LCP .380 ACP accurately at closer distances, but it's not as easy as my other, larger guns... particularly beyond fifteen to twenty feet.
3. Gun Families
I prefer and recommend gun families. If you're full-size gun is a Glock 17 or Glock 19, then if you want something compact you should get S&W M&P Compact... NO! Get a Glock 26 so everything operates and works the same. Going from my Ruger SR9 to my Ruger SR9c when I need a slightly smaller-sized gun to carry concealed is a complete no-brainer for operation and shootablilty while the full-size magazines work in either gun. The other thing I like is that I can buy a holster for my full-size SR9 and it works perfectly with my SR9c since the barrel is just a bit shorter, but the shorter grip of the SR9c is really what makes it print less for concealed carry for me.
Revolvers are the same way, all my Ruger revolver cylinder release buttons work the same and the cylinders all rotate the same direction. I will make an endorsement of the Ruger LCR if you're set on a light-weight, snubby. It seems to have less recoil with the same +P rounds than S&W Airweights and the Ruger LCR has the best out-of-box, double-action trigger pull I've ever tried.
4. Test Drive
I'm amazed at how many folks go out and buy a gun that they've never shot before... and I have been one of them in years past! I tell students who are thinking about buying a new gun and want to take my NRA/Ohio CCW courses to wait on purchasing a gun until they get through my course. That way they are armed with knowledge and they also have an opportunity to try just about any size gun and caliber they want with our collection the gals and I have built up over the years.
If you're thinking about buying a gun, at some point you need to quit reading web reviews and watching YouTube. Go to a range that rents the guns you're interested in or find a gun friend or instructor that will let you try the gun out... not just fondling the gun at the gun counter in the local gun store, but actually pulling the trigger and feeling the "BANG".
5. Practice and Training
You need to practice and train with your handgun. If you're primary handgun and ammo choice is such that you can't shoot a hundred rounds in the course of an hour on the range at least once a month, you need to rethink you choice. Whether it be the recoil is too painful or the cost of ammo, if you can't shoot and practice regularly, you've probably chosen the wrong gun.
Also, make sure you run your self-defense ammo through your gun in a decent quantity to check relaibility. I meet too many folks carrying handguns with ammo they've never actually shot through the gun because good defensive pistol ammo rounds run about one to two buck a piece and that's too expensive to practice with. Folks, your life depends on it! Which again, is another good reason to be lookin' at the 9mm or .38 Special.
There are a lot of things to consider if you're looking for a first gun or another gun to carry concealed or use for self-defense. The best advice I can give you is don't just go by what someone else tell you, but educate yourself, check the guns out yourself, and try the guns out yourself... so that way you'll develop your own... pistol Packin' Pickin' Priorities...
Well folks, those are some of my thoughts... how about some of yours in the comments...