I had a rubber-coated airgun stock that went horribly sticky. Like the OP, I couldn't find a cure (though, unlike him, I didn't consult the SD oracle). In the process of trying, the rubber began to peel off, revealing a nice bit of walnut underneath. It took some work, bit with all the rubber and adhesive finally removed, and the walnut given a nice oil finish by a friend, the result is most pleasing. I'm guessing they picked out that particular piece for rubber-coating because there is a major knot in a prominent place that they considered an eyesore. All it lacks now is some chequering or stippling, something I have no expertise in.
