IF you take out the stereotypes and how little some people know, you find that the 32acp is not a bad gun for self defense. The diameter of the 32acp bullet is .309 vs .355 for the 380/9mm/38/357. Basically, 12% smaller. That is the only real disadvantage. The importance of any pistol bullet is penetration. A FMJ 32acp, on average, will penetrate between 13-16 inches. This is more than enough penetration; according to just about ANY authority or so called expert.
Bullets are a catch-22. Bullets are invented with greater weight, to increase penetration. However, as modern propellants were developed, they realized that these same weight bullets could then OVER-Penetrate. Some pistols cartridges, like the 45acp, were a small enough casing, that they still maintained their 850-950 fps. With a LRN, the penetration was in the 12-14" range. But with the 9mm, 38spl, 357 mag, etc.... the additional velocity with standard fmj/lrn type bullets pushed them too deep.
Then, hollow points became a very popular bullet. They achieved 2 things. Most important, they did the parachute effect and slowed the bullet down so it wouldn't over-penetrate. Also, by shear force, it expanded the bullet. Any increase in diameter, means more potential tissue damage. Assuming of course that you don't give up on penetration. I.e. a 45acp doubling in size may sound great, but not if it only penetrated 4-5 inches. Well, unfortunately, Hollow-points had their catch-22 also. Not enough velocity, or quality deficiency, or "Clogging effect", and the hollow point won't expand. Then the hollow-point is a toss up. it "MIGHT" act like a fmj/lrn and penetrate very well; or it slows down too much. So, to have the best odds, modern bullets with hollow-points tend to push the 1000+fps. All the way up to around 1400-1500 fps; depending on the caliber.
Now; does this mean that a 32acp can't be an effective defense round? No, not at all. Doesn't mean it's equal to or better than a 380, 9mm, 38, 40, 45, or 357; just that it can be effective. If your accuracy with a 32acp is 9.5 out of 10 compared to 6.5 out of 10 with a 40s&w, then the 32acp is actually more effective than the 40s&w. What is important, is to not try and make the 32acp what it is not. Don't use a ford focus to hall trash to the dump. Don't use a ford F250 single cab to take the family on a summer vacation.
With the 32acp, use fmj or LFN (Buffalo-Bore). I prefer the Buffalo-bore or the winchester flat nose. They create larger entrance holes and more tissue damage. They don't slip/slide through like most fmj do. They still penetrate acceptably from 13-16 inches. And contrary to those who don't know what they're talking about, they don't just "Piss someone off".
Now, if you live in the northern states, where there's a lot more layers of clothing; e.g. heavy coat, sweatshirt, and undershirt; then the 32acp probably doesn't have the mass necessary to penetrate the 13-16 inches. And therefor, it will be much less effective. But if the environment you are going to use it, is a typical single layer of clothing, then there is absolutely nothing wrong with using a non-hp 32acp.
People who swear against this, truly do not know what they are talking about. Of course, if a person's position is 1) recommending a single gun for multiple purposes; 2) Paranoid into believing that they need 10+ rounds in a magazine; or 3) Carrying the most powerful handgun that an individual can possibly handle, because you never know what the scenario can be; then these people will never even consider a 32acp. And there is nothing that anyone can say or prove that will get them to see the facts and admit it.
But again, it's all about perception. The 32acp is most definitely an acceptable round for self defense; if used properly. When I'm at a dinner party, carrying a 45acp or even a 9mm concealed can be very difficult because of the attire. However, a 32acp or 380 in an ankle holster is small and light enough to be useful. When you get to the size of guns like the LCP, Seecamp, Kel-tec, kahr, etc... the higher the caliber, the more difficult it is to shoot accurately. I will guarantee my 7 shots in my walther or FEG 32acp will be dead on target at 10 yards; compared to the same 7 shots out of my kel-tec 9mm. However, there are times the 32acp just isn't the appropriate round. I believe that most 32acp proponents understand the limitations. The 32acp critics however, refuse to admit that the 32acp actually has some advantages. And sometimes, the advantages outweigh the disadvantages.
We don't carry a 12 gauge because it's not practical. We compromise by carrying a pistol. And even the 44 magnum has disadvantages over the 12 gauge. However, the 44 mag has some advantages over the 12 gauge. Well, while the 45acp and 40S&W have advantages over the 32acp, the 32acp does have so advantages over the 45acp and 40s&w.
Personally, I don't expect that it would take much, if any, fewer for larger calibers, though. Not that I would necessarily know the difference anyway, should I ever be forced to shoot a bad guy, since they'd get 3 quick shots right off the bat no matter what, the third one aimed at their head (assuming that the shots hit where they're aimed, of course, and it isn't that easy in a real shooting).
