The question:
So I have been debating with a friend of mine survival handguns. Me and My wife both would carry a handgun in the event of some kind of Teotwawki situation. The question arose whether it would be better to carry firearms with a compatible caliber (same Ammo) or whether to diversify and carry different calibers. I can see Pros and Cons of both. So I figured I'd pose the question to my favorite survival blog site. What do you think? - Flip057
Thanks for the question!
When it comes to full/"service" sized handguns, performance is fairly similar across the board when using modern hollow point ammunition. You get very similar penetration and expansion, whether it is 9mm, .40 S&W or .45 ACP. All handgun rounds are a compromise and not particularly effective when compared to a long gun, which is why you hear people say things like "your handgun is for fighting your way to your rifle." There isn't a huge relative advantage to carrying one or the other--the performance characteristics aren't so different that there is a pressing need.
If you are scavenging/bartering for ammo in a post apocalyptic world, there is a small advantage provided by being able to shoot two different rounds. If you've got a 9mm and a .45 ACP and all you can scrounge up is .45--that kind of thing.
However, that small advantage is outweighed in my mind by the disadvantages of to having to stock two different rounds--more to stockpile and no ammo compatibility between the two firearms. You also rule out the possibility of having two weapons with interchangeable magazines. If you get into reloading, you need to buy components and dies for two different calibers. If you're caching/stashing ammo some place, you now have two calibers to stash. Basically, the two different handgun rounds are an added level of complication for little added value.
I would generally recommend standardizing on a single round--generally the one you can buy cheapest and shoot the best. For most people that's 9mm, but your mileage may vary. If you can, I would also recommend choosing pistols with compatible magazines, too.
Individual circumstances could certainly dictate otherwise. If you operate in Grizzly territory, it could make sense for one of you to carry a .44 mag revolver. If you're bugging out on foot, where you have a limited ability to carry multiple guns, I could certainly see an argument for one person carrying a .22lr handgun and several hundred rounds.
Finally, the primary factor behind your choice of handgun should be how well you shoot the thing. If you shoot a 1911 like a champ and your wife is only comfortable with a target .22lr pistol, then screw something like ammo compatibility. Shot placement is what ends fights--especially with handguns--and if the two of you need different handgun calibers to get bullets accurately and quickly on target, then don't choose otherwise. However, in the vast majority of cases, you should be able to find a round that you can both shoot well.
