Loading old fiber base hulls is risky business in my opinion, as portions of the fiber base can come loose on firing and lodge in the barrel with potentially bad consequences if not noticed before firing the next shell. Although I haven't tried this personally, I'd have no compunction doing so; and that would be to coat the outside surface of your #57 primers with epoxy gel, then insert same into the primer pocket. Let the batch harden overnight; then load the next day.