For surivival situation, I'd probably go with my Ruger Frontier model "scout" Model 77 Mk II in .308 Winchester with intermediate eye-relief scope.
It is lightweight, short and handy. Rifles are carried more than they are shot. The rifle is quick to the shoulder and will be pretty close to ideal once I put a ching sling and a timney trigger on it.
I have a goodly supply of BTHP 168 grain Remington match ammo for it, followed by smaller amounts of older government match ammo, and South African surplus ball.
Second choice would be my Miltech-reconditioned M1903 Springfield with a Tanner Saddlery M1907 leather sling and bayonet. I have about 1000 rounds or so of 30-06 ball and close to 400 rounds of black tip AP.
I don't think I would go with one of my semi-autos. Too dependent on spare parts and lubrication. Bolt-actions for sure.
Once you've got your sights adjusted to the ammunition you have, step away from the bench. In competition or the field...there are no benches.