I would be reluctant to seal a carbine and leave it. I know individuals who did this and they had massive damage to the weapon when they decided to take a peek and see how things were holding up. The Army went to great lengths to perfect a system for long term storage. If you look at NOS M1icon Garands, they were simply coated with preservative, wrapped in paper and put into a wooden box. Enclosing a weapon in a non breathing plastic wrapper is asking for rust in my opinion. You can buy dehumidifiers (small heaters) for gun safes. Mine has two although I never plug them in. Keeping a weapon rubbed down with light oil works very well. The secret being to always wipe them off after handling and making sure some oil remains in the pores of the steel.