Re: Thoughts on a .40 cal
A 9mm will do pretty well for SD but a bigger caliber is better as long as a person can deal with the recoil and get off those secondary shots on target. It's as simple as that really. If you're just target shooting you might as well use a .22. For SD give me as much gun as I can handle as long as it has the right characteristics. I switched from .45 to .40 because of more ammo per mag and because of better penetration through steel and angled glass i.e. a car door or windshield. 9"s are good for penetration too because they are smaller rounds traveling fast. But the size of the bullet means deeper penetration in tissue. It's a physics thing. Mass, deceleration and all that. Yes speed is a factor but tests tend to indicate that bigger bullets penetrate tissue deeper just as smaller bullets penetrate steel better. Newton just didn't cover all this ground but modern terminal ballistics testing has covered it. IMO a .40 is a good compromise between the good things of a .45 and a 9mm and it has the high capacity (almost) of the 9mm. I don't plan on missing much either but I'd rather not get killed for lack of shooting back as Clyde the one armed deputy in "Unforgiven" said, "I just don't want to get killed for lack of shooting back."