This is a controversial topic sometimes, so I will preface this with: This is for those of us who WILL keep a store of ammo, not whether or not we should.

That being said, who keeps a lot of one caliber and who keeps a variety? I've contimplated this and came up with a number of possibilities. Obviously, bug in is less of an issue than bug out.

The first: .22 long rifle. Obviously takes up the least amount of room, is portable in larger quantities, can take small game for subsistence, but MAY be lacking for larger game at distances, or protection at those same distances. Works in long guns and hand guns.

.12 gauge, probably 00 buck. Good for most mid to large game, very good for protection. Takes up a lot of room, and is not very portable. Not much left to small game once you're done. Limited range capability.

.223/30.06/.308/other large caliber. Great for protection, arguments pro and con for larger game. .223 offers some portability in quantity. All have long range performance.

.44mag/.357mag: I have lever action rifles and revolvers in both calibers. This gives me a lot of flexibility, and allows for carrying one caliber to be used in both. Also allows for two people in my group to be armed with one caliber. Range is very limited. Portability is ok, but not great. At this point, this is my last resort, bug out, can only take what's on your back option.