Back40,
The best weatherproofing you can do for that wooden stock is to disassemble your Tikka, removing barrel, receiver and trigger group. Next, get yourself a good car paste wax.... the stuff with lots of carnuba wax content....or Johnson's Paste Wax and start slathering on that paste wax on the stock in every nook and cranny you can get into. Don't forget to put it on the barrel and receiver as well. Rub it down with your hand and fingers and do it again, buffing it up with a soft tee shirt. Make sure to get into the barrel channel and trigger/clip cutouts. When you're done, re-assemble the gun and you should be set for the worst conditions.
Jim