Is that inner rod brass or steel? Steel on that rod, wasn't it? You bet they'll rust quick if exposed to bp, pyro, or T7. Pays to clean everything - even the parts you wouldn't believe could be exposed. Did they ever fix the Optima rifles so that you can clean the firing pin area (without removing the buttstock)?

The Hunter Super Rods have one steel piece inside that jag (the worm part). You'll need to unscrew the jag from it and wipe it down on occasion, else it will corrode on ya. I have yet to use the worm on mine so I suppose it wouldn't be any great loss.