A ‘takedown’ gun is something that you can easily take apart and store, for example, in your car, or your backpack. As a survival gun, it allows you to be ready and easily at hand whenever you are in a bad situation far away from any help.
As a camp gun, it is at hand to dispatch vermin, or to go after small game. However, in both cases, the notion is, that you can use something bigger either for big game, or for any kind of unwelcome predators that might come sniffing around your camp when you least expect them.
In general, rifles for these type situations are rimfire and the ammo is small, light and cheap.
You can stock up on it easily and have enough of it handy if you actually have to find your way out of the middle of nowhere. These takedown rifles can be chambered in .22LR, on up to and including 45-70 caliber.
While there are some really good rifles in this category, there are not as many as you might expect. However, the options that are available are pretty good.
You get to choose what preferences your gun has to fit including what you can afford, depending on the type of outdoors situation you might find yourself in.