Great stuff. I got to thinking about this after the recent tornados and being from the Midwest originally, I know how chaotic things get. I imagine a rifle might be one of my essential grab-n-go items as well as a bugout bag. I have my loaded mags, cleaning kit, extra ammo, a quick BLS first aid boo-boo kit, batteries for my flashlight/optic and one mountain house entre in case I'm separated from my main survival kit.
Range bag: Eyes and ears (and extras), gloves, towels (sweat rags!), soft items I'll need, like a sling. Ammo if I've got space.
Range box (cheap $6 tool box from Home Depot): Cleaning kit, ammo, mags, any tools I think I might need, packet of grease, AR sight adjusting tool, a couple of battlefield dressings, staple gun and staples and any other things I think I might need and will fit.
Rifle case (UTG case that looks a lot like a soft guitar case): My AK (Romanian kit, NDS-3 receiver, plastic stock, home-brewed single point attachment, TAPCO SAW pistol grip, Ultimak, Aimpoint Comp M2 on a low mount and a Mojo rear sight - I built the rifle with a friend's help), magazines, P226 or P220 or Ruger Mk II