There is much debate in the hundreds of firearms forums scattered across the globe in regards to the effectiveness of this or that firearm or particular caliber. These discussions venture deeper on occasion touching technologies such as bullet design, bullet weight, or even the manufacturer of a particular product. Being the engineer that I am, I realize that firearms are used in an environment that could be said to be stochastic, i.e. things occur at random, but sometimes at a given potential, i.e. probability that they will occur in a certain manner.
I will not link it here, but there is a blog out there authored by a gentleman who is now a former worker in a state crime lab. His blog summarizes various observations made conducting autopsies of both victims and perpetrators of gun related crime. As one would expect, many of his opinions derived from all those years cutting dead folks open were challenged. I do not by the way disagree with those challenges, but keep in mind they are challenges of a future context when a particular weapon is to be used. They cannot change what happened with the dead body on the autopsy table.
A scientist, an engineer , or a reasonably trained individual realizes the autopsy table is the place where empirical data is derived. Someone committed a gun crime in real life and was successful in killing someone. The person responsible for the dead body may have of course been a law enforcement officer or even you defending your home.
Taking advantage of our above empirical approach to weapons and dead bodies, one can observe that a percentage of those dead bodies came to that state via Law Enforcement specific ammunition, as well as law enforcement ammunition a private citizen can purchase. Think of 9mm Luger, .40 S&W, and 45ACP in Winchester’s Ranger T (successor to the Black Talon) when considering ammunition intended for law enforcement bu available to Regular Joe. Think of Federal’s Bulldog Home Defense in 45ACP when thinking of Regular Joe obtaining the low pressure version of Federal’s 45ACP +P Expanding Full Metal Jacket Law Enforcement ammo. While one can obtain Ranger T in 45ACP +P and 9mm +P+, one cannot purchase the +P version of Federal’s EFMJ 45ACP as Regular Joe.
Along the lines of what should happen when using something like the Federal EFMJ ammo, we typically envision a scenario where a full metal jacket is desired for penetration of materials surrounding a perp, but expansion is desired so that the round remains “in the perp,” provided the shooter has beat the odds (randomness) and actually hit the perp. But guess what? Federal has recorded a failure where an officer shot a perp in the head and the perp kept retreating away? Why? It was that metal skull plate that deflected that soft rubbery tip on the EFMJ round. (Yes, the perp was later caught and this was reasonably determined.)
Patrick Whaley, a Georgia Tech student, was sot in the right side of the chest some two or more years ago with a 9 mm semi-automatic. One would expect a shot to the right chest to kill a man, even if the bullet passed through the right side of the chest as in Patrick’s case. Probabilities, probability distributions, victim body weight and general mass distribution, clothing worn, jewelry worn, metal wiring in the ribcage due to bypass surgery, a cell phone in the pocket; we all understand that the interaction of the above items mentioned can affect a projectile flying forward, released by a delivery mechanism (a gun) with the intent to injure or kill.
None of us can predict the future. We can attempt to increase the probability of success when defending self, friends, and family. If you don’t think so, let me shoot you with my S&W 500 and we’ll allow the man standing at the autopsy table to collect empirical data. (It’s a joke folks. Although perhaps effective at making a point.)