Count it as a lesson learned (the hard way): Always, ALWAYS, remove the wood from EVERY gun you buy, including taking off the buttplate and PG cap (if it has one) - and soak the uncoated interior surfaces of the inletting and under the buttplate with TruOil until it will accept no more oil.
Neglecting to do so invites the wood to absorb moisture through the unprotected grain & endgrain, and it will swell until it dries out - sometimes permanently wrinkling the stock's outer finish, especially if it has a polymer in it, as the polymer will stretch with the swelling, never to return to it's original size.
It will make no difference, at all, what specific type wood is used for the stock. All wood is a natural product, and will react to moisture/water, period.
NO Manufacturer finishes/protects unseen/hidden wood surfaces.
Strip the stock with some Formby's Furniture Refinisher (from WallyWorld), lightly sand any remaining imperfections, stain it, then TruOil the wood, inside and out.
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