Try this
http://opencarry.org/
This is to the open carry forum about Oregon, should find everything you need there
GP is pretty loose, but out of state plates draw a lot of attention.
If your into AR's look up John Noveske, one of the best AR makers period.
Check out Sportsmans Park just north of GP, probably one of the best shooting & archery ranges in the North West, it's county run, but a good place. Gp hasn't succumbed to being politically correct.
Try to go rafting on the Rogue River if you can, lot's of outfitters there to take you, fun fun fun.
I wouldn't leave a rifle in a rack unattended, unfortunately there are a lot of tweakers out there, even in the boonies. Personally I wouldn't go into the boonies without a firearm, just don't leave it in plain sight.
When you see the JoCo the Caveman in GP tell him WalkenBear says Hi!