Jed, you might want to do a search of the Gunsmithing forum and read some of Sitka's stuff on Oil over Epoxy finishes. You'd have to strip the oil finish and start over but if you really want to have the most waterproof finish you can have on a wood stock Sitka's convinced me it's the way to go.
I've been using "CPES" - Clear Penetrating Epoxy Sealer, that I got from Japan Woodworker but I think Sitka has another one that he prefers.
Sitka, All of my Kimber wood stocked rifles have had finish on the inside of the barrel channel, just oil like the rest of the stock but it was there................................DJ
