If our society really, really goes into the tank, people should consider a back up weapon if the modern ammo one needs is gone. I have a reproduction Remington 1858 revolver and a repro Zuave with reproduction Minie bullets and plenty of black powder and Pyrodex. I do need to get some caps.
Consider some surplus weapons with NATO ammo calibers like the http://www.the-armory.com/shopsite_sc/store/html/Russian_M44_Rife.html
Mosin Nagent