I would stay away from the 770, it is Not a Remington 700. It's a entry level rifle that has not been getting good reviews on the forums. In that price range I'd look at the Ruger American which has been getting excellent reviews or even the Savage Axis line. I think most of the 770 complaints are centered around bolt cycling issues and feeding issues. I believe the bolts are prone to binding in the receiver when cycled. Would probably be ok as a hunting rifle but as a SHTF rifle I wouldn't recommend it.
-Infidel
-Infidel