What I did to my scope to help protect it was after making sure it was very clean and free of any black powder crud, I wiped it down with denatured alcohol. After I was sure it was dry, I took black plastic electrical tape and started covering all parts of the scope except the adjustment nob and the magnifacation dial (and the lens of course )

After I shoot you can take a wash cloth and that black powder crud will wipe right off that plastic tape. When the tape starts to look worn, remove it, wipe the scope down and put a new layer on. The last wrapping has lasted over two months, and I SHOOT A LOT!!