re: Handgun - Knockdown Power vs Concealment

“Knockdown power” is a myth created by Hollywood movies literally knocking down people with a shotgun blast. None of that would happen in real life. And while I get that using the term “knockdown power” casually doesn’t necessarily imply this blatant ignoring of the laws of physics, it perpetuates bad information.

The terms you’re looking for are “muzzle energy” and “terminal performance.” Both more accurately describe how defensive rounds can incapacitate and “knock down” an attacker by causing blood loss, bone breakage, or damage to the central nervous system.

As for your question pertaining to .40 and .45, I’ll tell you what I tell all my students in my concealed carry classes - 9mm Luger, .40 S&W, and .45 ACP all pretty much do the same thing given you’re using tested and proven hollowpoint ammunition. One is light and fast, one is heavy and slow, and the other splits the difference. As for 12 gauge, it is certainly way above your standard handgun service rounds for terminal performance.

As for my personal preference, I carry 9mm for two main reasons: higher capacity and faster follow-up shots. As others have mentioned, it’s far better to learn to put shots quickly onto a silhouette target than to only shoot a bullseye with something like a 44 magnum. While the fundamentals of accurately shooting a handgun are important, for defensive handgun use it’s better to be fast and relatively accurate. Ultimate precision doesn’t matter as much as long as you’re hitting your target - I don’t care if I hit the left ventricle of someone’s heart, I would just prefer to hit them center-of-mass.

Sorry for the rant and you may have not meant it exactly how I presented it. Thanks for bringing up the topic.