In the handgun forums and magazines, a new narrative holds that .45 and 9mm are virtually the same in “stopping power,” so we should all carry the 9mm for its (relatively) lighter recoil and larger cartridge capacity. While lighter recoil and more ammo are certainly good reasons to go to a 9mm instead of something larger, are smaller bullets really as good as bigger bullets?
The answer, of course, is “it depends on the bullets.” Historically, it takes superior bullet design and/or higher velocity for the smaller bullet to do as much damage as the larger. The smaller round is much more demanding of careful ammo selection, in my experience. Any deer hunter will tell you that you have to carefully select .243 loads for quick, humane kills on deer, while there is a broader spectrum of .308 loads that will do the job. Any soldier with a specialty in small arms will tell you that much more money and research has gone into making effective anti-personnel ammo in 5.56mm NATO than was ever needed for effective 7.62mm NATO. In the same vein, while I’m usually perfectly comfortable carrying a 9mm for personal protection, I’ve found myself having to be MUCH more picky to find street proven ammo for that chambering than for my old favorite .45.
I’m not alone in that. A fellow writer, Charlie Petty, wrote 25 years ago in American Rifleman magazine of FBI’s research at the time, “As the testing progressed, another factor became obvious. No 9mm loads came close to the 10 mm and .45. ‘We expected that there would be a gap,’ said (FBI’s Urey) Patrick, ‘but we didn’t expect it to be so large.’ In the first series of tests, the best a 9 mm could do was 67.5%. The .38 Spl. fared just as poorly, and the standard FBI-issue .38 Spl. (158-gr. lead hollow-point +P) also achieved a 67.5% success rate. Among the initial rounds tested, only the 10 -mm, .45 ACP and a single .357 Mag. round were able to score consistently above 90%.”
Time went on. Ammo got better, and the new designs probably benefitted the 9mm proportionally more than the bigger calibers, but all were made better. A famous wound ballistics specialist whose work was pivotal to the FBI’s testing protocols was Dr. Martin Fackler, who died last month. In a 2012 interview Dr. Fackler said, “The size of the hole the bullet makes, the .45 is bigger than a nine-mill. But how much bigger, by diameter, it really doesn’t give you the measure of how much tissue it disrupts. What does is the area of a circle. Area of a circle, it was pi-r-squared. It’s the radius squared. So, if you take your .45, your point four-five-one and your nine-millimeter as your point three-five-five, take half, take the radius, square that, and what you’ll find is that the volume, or the area, of damaged tissue made by the .45 is about sixty percent more than made by the nine.”
Another recognized authority, Dick Fairburn, recently wrote in Police One.com, “I will always carry the largest drill I can, so my choice for open/duty carry is either a .45 for social work or a full-power 10mm in the boondocks. When I need a small pistol for concealment, a 9mm with high-tech ammo will do.”
Bearing in mind that where the bullet strikes is probably more important than anything else, and there is a wide range of experience and ability to control rapid pistol fire, I’d be curious to hear what all y’all think about this. Since this tends to be a very contentious topic on the gun related internet, I’ll remind everyone that informed opinion, experience, and facts are welcome here, and ad hominem argument is not.