|Not actually Erin.|
Picture by KJ Photography
& is used with permission.
While I touched on firearms that fired different types of cartridges in my first Apocalypse Arsenal post (and I recommend all those for this category as well), this post is more along the lines of "Let's have your long gun and sidearm each take the same caliber to simplify your ammunition demands, and if those firearms can shoot multiple types or calibers, so much the better."
There are multiple choices here, and I'm going to admit my bias by starting with my personal preference:
Kel-Tec Sub-2000 and Glock pistol (either 9mm or .40 S&W)This is my home defense loadout, bought specifically because 9mm is the most common self-defense ammunition in the United States (something like 90% of all police departments use 9mm) and Glocks are the most commonly-issued pistols. This means that parts and ammunition for them are plentiful and relatively cheap now, and in the case of a catastrophic collapse or disaster ammunition and magazines should be relatively easy to scavenge.
What's more, any magazine that fits the Sub-2000 will fit your Glock (although not necessarily vice-versa; magazines for the Glock 19 and Glock 26 will not fit a Sub-2000), so in the case of magazine loss or malfunction you can load one from the other. Also, those 33-round extended magazines work really, really well with the carbine-length Subbie.
Finally, both the Sub-2000 and Glock pistols come in .40 S&W as well, if you want a bit more oomph in exchange for increased expense in ammunition & magazines.
Beretta Cx4 and 92FS
A similar loadout to the above, only using Beretta's proprietary magazines. The bad news is that you'll pay more for the guns and magazines; the good news is that you can still use 30 round magazines in both. The good news is that the 92FS is the sidearm of choice for the United States Army, and has been for over 20 years, so the same rule for buying and scrounging applies. Both also come in .40 S&W.
- For as long as they're in business, Hi-Point will guarantee your firearm for life and will repair it for free.
- This may be all that someone can afford.
- In an emergency, any gun is better than no gun at all.
Marlin Model 1894 Cowboy and revolver in matching caliber
If you get the .357 Magnum chambering, you can also shoot the less-punishing and more-plentiful .38 Special cartridges in it; if you go .44 Magnum, you can also use the less-common .44 Special. Get a revolver to match (and there are lots of these) and you're all set.
I almost mentioned getting one of those pistols that can shoot both .410 shotshells and .45 Long Colt, but investigation into similarly-chambered carbines did not fill me with confidence -- either there were questions of reliability, or a choke/sleeve had be used depending on the ammunition, or both. I'd love to find a reliable rifle that can fire both types without needing sleeves, and if it can use moon clips to shoot .45 ACP, so much the better.
Once again, I reiterate that these are simply my opinions; you are free to disagree with me. What I present is A solution, not THE solution. If you believe I am mistaken, please leave a comment below and we can discuss it.