Walking? Pffft. That's for the Marines.
Death before dismount.
That being said, there were times when I told myself that a full sized M-16A4 would have been great, it was shortly followed by father's voice echoing in my head saying "When your in charge, take charge." and then remonstrating myself that Danny was pretty damn good with his DMR.
NRA Life Member
Me: "The .45 GAP was an answer to the question nobody asked."
Trooper pal: "Says the guy who thinks .38 Super and 10mm are viable pistol calibers and gets mad when Wal-Mart doesn't have them."