I made the mistake of wiping the grip/grip-cap area on an Ithaca SKB shotgun with WD-40. When I next checked, the cap (plastic) had warped upward away from the wood. I no longer get WD-40 anywhere near guns.
My Father in Law had an SKB Ithaca 900 shotgun where the plastic cap had warped away from the wood too. He kept WD-40 around his work shop. I always thought it must have come close to a heat source. Your experience makes more sense.
