A SIG 510 for battle rifle application, a SIG 550 for CQB, where the
.223 ain't too much of a liability rangewise (when I score a hit, I
want the target to be completely dead).
If I were in the US when SHTF, I'd grab the next-best AR since I know
how to handle the rifle, trained all the failure drills etc, and then
I'd aquire a FAL, or a Garand to get some range.