>>246208Continued.
>Do you think I can manage with the -5° bag for the whole trip or will it just be an ordeal in the warmer states?That bag may end up being a little too cold if you plan to start in early to mid March. Snow storms and temperatures around 0F-10F are not uncommon on the AT during early spring. If you wear extra layers inside the sleeping bag though you'll probably be OK, but you may have a few nights where you're not totally warm.
>As I come from germany and I don't have any relatives/friends/whatsoever in the states I won't be able to use the "mail drop" technique to supply myself with equipment along the trail. Or would it work?A mail drop would work if you ship them to hostels along the trail. Many hostels will allow you to mail things there provided that you call ahead and make those arrangements. I advise against shipping to post offices because they close early usually (before 5pm in most cases) and are not open at all on Sundays.