Well one could wrap the rodent-rocket in duct tape once finished packing the propellant charge, fuse, and any warhead inside. That could help provide some additional resistance if using something like a flashpowder charge and make the rodent-rocket go off with a louder 'bang!' once launched.
Its one...small...step...for a gopher.
One ...giant.... leap..for gopher kind
We shall get a gopher to the moon, or it'll die for our trying

Bet me and Lit could have some fun working on that one as a weekend project xD