Ideally it will only be loaded for a couple of hours before unloading it on a nice buck.

But should real life interject on your fantasy, here's what I do.[:@]

Clean the barrel with acohol/windex mix and dry patch really well.
Load and place electrical tape over the muzzle. (shoot through it no problem)
Capped when hunting (inline or Perc) (plugged with a toothpick for the flinter)
After the hunt I'll use a fired cap on the breech plug to keep it sealed for the inline but I blow out with a CO2 un-loader for the flinter and percussion rifles and reload in the morning.

I've had my inline Omega loaded for 2 weeks in really crappy weather and it went off without a hitch. I use 2f T7 in the inline and 3F Goex for the others.

Good luck this fall.