Seems we focusing on subsistence survival where the gun's main use is food gathering. So I will bring this up....
I was saving this for a future thread, but for my aforementioned Spartan/Baikal SPR 94 combo gun in 12 ga & .223 Rem, I am ordering chamber adapters which will allow .22lr in the .223 chamber, one for .22 mag, and one for .22 hornet.
So, once I get these chamber adapters, with this gun I'll be able to shoot:
1. Anything 12 gauge from smoothbore, with all that that entails
--Foster slugs
--Buckshot
--Birdshot
(so already we can kill anything on earth, standing still or moving, except maybe a blue whale. But range is a bit limited).
2. .223 Remington for long shots on small, medium, and large game. And with a heavy bonded bullet and a head shot, there's virtually nothing on earth that cannot be killed with this.
3. .22 hornet for small and medium game
4. .22 magnum for small game
5. .22lr for small game, with very lightweight & cheap ammo
I can also shoot .22lr shotshells and .22 magnum shotshells through the .223 bore with the chamber adapters. With these small shotshells, you can shoot "tweety birds" without destroying much meat, and the reality is that tweety birds are the most common and easy to find/easy to hunt edible protein in the wilderness, so this is an important point.
Store the chamber adapters in a stock cheekpiece unit with a zipper pocket, and just cannot possibly get any more versatile. I don't think there's any way to say that any other gun is better for the food gathering / subsistence survival scenario.
Let's not forget that the vast majority of shootable meat/protein food in a real survival situation are small, smaller, and smallest in size, where the .308 scout rifle will blow them to smithereens, leaving no meat. Raccoons, beaver, opossum, groundhogs, armadillos, turkeys, ducks, quail, doves, crows, tweety birds, squirrels, rabbits, rats, mice, voles, gophers, etc. The scout rifle or any "full-powered" rifle chambered in .308 or similar may be an excellent choice for survival where self-defense is involved, it is an exceptionally poor choice (relative to the alternatives) for subsistence/food-gathering survival (and incidentally, both are inferior to a fishing pole & some snares - if you're limited to either/or for some reason). You might hit the jackpot with an ungulate (deer), or you might go a whole season without getting one, as I have done in the past. Dunno about you, but I cannot survive 3 months without food. Tweety birds will taste mighty yummy after a mere 3 days in the woods - and tweety birds take all of about 5-10 minutes of sitting still to see and shoot one.