“It’s not the size mate, it’s how you use it.”
Nigel Powers, Super Spy
Austin Powers in Goldmember (2002)
Wise words for a comedy movie and certainly relevant to the never-ending caliber wars.
- What caliber is best for concealed carry?
- If I use a 9mm, won’t the bullets just bounce off my attacker?
- If I choose a .45 ACP, is there a chance that I might inadvertently destroy nearby buildings?
- Which buzzwords do I have to consider? Knockdown power? Stopping Power? Incapacitation? Penetration? Constipation?
When we start talking about all this stuff in theory and spice it up with Vietnam anecdotes, we cause ourselves a lot of unnecessary grief. “When I was in ‘Nam, Charlie snuck into my foxhole one night. I plugged him with one shot from my 1911 and it knocked him 123 feet in the air right into a low flying F-105. After that, .45 is the only caliber I’ll use.”
OK, so maybe I’m making a bit of light about the value of anecdotal data, but anecdotes are exactly part of the problem in the great caliber debate.
- “I heard…”
- “I saw a Youtube video of a guy getting shot and he didn’t even know it.”
- “I saw a youtube video of a shooting and the guy fell down after the first shot.”
- “When I shot that deer, it cartwheeled 17 times.”
And so on.
There are far too many variables at play to compartmentalize ammunition effectiveness into nice little mathematical buckets. Handgun bullets make holes. No more, no less. Some holes are slightly bigger than others, but when you really start comparing diameters of the popular handgun calibers, we’re not talking orders of magnitude of difference. Let’s consider the range of self-defense calibers from .380 ACP to .45 ACP.
If we’re talking about unexpanded bullet diameter, common self-defense projectiles range from .355 to .451 inches. That’s a difference of only 0.096 inches. That’s less than the thickness of two pennies. If we’re talking expanded bullet diameter, assuming 1.5x expansion performance, then the range is .5325 to .6765. That’s a difference of 0.144 inches, which is the same as a penny stacked on a nickel. Yes, bigger bullets make bigger holes, but I mention these numbers to put things in perspective. A small fraction of an inch diameter wound channel difference isn’t all that significant in the context of a six-foot tall, 200 pound irritable bad guy.
When it comes to energy or the ability to destroy tissue, an “average” 9mm defense load might deliver about 400 foot-pounds at the muzzle. An “average” .45 ACP defense load would unload about 425 foot-pounds. While that may sound like a lot, it’s not.
If you consider momentum, the ability to penetrate and move things, a 9mm load will present about 21 lbs-ft/second and a 45 will deliver about 30 lbs-ft/second. That level of pure momentum is roughly equivalent to hitting someone with a gallon of milk moving at three and a half feet per second.
Before folks get all upset, I’m not equating getting shot to getting bonked with a flying milk carton. While the milk will make a big mess, it’s not going to kill you unless you bought it at Food Lion. My only point is that handgun bullets just don’t have all that much pure energy – at least not enough to make people fly across rooms and explode. They hurt, they can incapacitate, they wound and they certainly can kill, but they won’t physically launch people through walls and windows like in the movies.