Oil is lighter than water. Sure, the raindrops pelting oil will dislodge it and get underneath. In a HVAC equipped house, a light coat of oil will keep the goblins away.

I usually store mine in a safe with a heat rod to control the humidity. they get a silicone wipe down out and a light oil wipe in the bore. A couple of patches wet with carburetor or brake cleaner followed by a couple of dry patches usually results in the first shot printing right where it left off last time.

jack


"Do not blame Caesar, blame the people...who have...rejoiced in their loss of freedom....Blame the people who hail him when he speaks of the 'new, wonderful, good, society'...to mean ,..living fatly at the expense of the industrious." Cicero