More:Well into the first half of the last century, defensive shooters had some very good handguns to choose from. Unfortunately, the developments in defensive ammunition had not kept pace with handgun development. For the most part, defensive handgunners had to make do with lead bullets for their revolvers and full-metal-jacketed bullets (FMJ) for their semi-autos. Neither was considered very good at stopping criminal attacks.
The defensive shooter should not be concerned about killing an attacker, but in stopping the criminal attack as soon as possible. Immediate incapacitation works best when there is adequate penetration—some 15 to 17 inches—and expansion of the bullet. Bullets do their job when they cause internal bleeding, thereby reducing blood flow to the brain, or when they impact the central nervous system. In either case, it is bullet expansion and penetration that get the job done.
Lead and FMJ bullets were generally OK in the penetration department. In fact, they were often too good at that job, resulting in the bullet exiting the bad guy and presenting a danger to others nearby. At the same time, they rarely expanded enough for it to be worth mentioning. Even if the bullet hit a major bone, bullet deformation or expansion was relatively minimal.
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