I have 4 22lr rifles:
1) CZ 452 Special. This goes to the range most often. The only changes I've made is to replace the rear sight blade (The part of the tangent with the notch) with a peep sight blade, and to replace the plastic magazine well with a steel magazine well. At 100m I have a reasonably good chance of getting a head shot on a large jack rabbit. At 150m ditto for a body shot. This makes it my best foraging rifle.
2) Ruger 10/22. Barrel upgrade, trigger upgrade, peep sights, Tactical Innovations 30rd magazine. This rifle is combat accurate out to about 100m. Presicion isn't really there.
3) Taurus M62 Youth Carbine. Simple and reliable, no modifications. Extremely short over all. A good compromise between the Ruger and CZ.
4) Springfield Armory M6 Scout. 22lr upper barrel, .410 lower barrel. Rear sight was milled off and replace with a short weaver rail. Rear peep sight attached. Sights set at 25m for both barrels. This is one of my SHTF/TEOTWAWKI rifles. As a foraging rifle, I can take anything up through medium game, and might do in a pinch for large game.
I know the M6 is sort of cheating as far as this topic goes. For a long term primitive camping trip, The CZ452 would go along, because it is my best small game forager. But for SHTF/TEOTWAWKI I think it's just too bulky.