If, for instance, the super volcano beneath Yellowstone blew, and I had to fend for my family--to at least some extent for at least some time...I'd want:
A Browning BL 22
Then a shotgun-A Benelli,
Then a real rifle! Maybe the R1 in .338, maybe...
If I could add a 4th it'd be a Barrett in .50BMG
or maybe a Remington Sendero in .300 Win Mag for accuracy.