If the stock is not valuable, just remove the metal and run it through the wash cycle of the dishwasher with dishwasher soap, BUT DON'T DRY IT IN THE DISHWASHER. THAT WILL POTENTIALLY CRACK THE WOOD. Keep the handguard on the top rack because it is more prone to crack. I have done this on several rough stocks and they come out pretty white and some of the dents are gone or smaller because the water and steam raise the grain of the wood. The moisture fills in the cells of the wood. If there are stampings on the stock you want to preserve, put a piece of duct tape over them and they should survive the dishwasher. After the wood is air dried, then I use 2-4 coats of pure tung oil cut 50/50 with pure mineral spirits. Let each coat soak in for about 20-30 minutes and then wipe off the excess and let the stock dry for 24 hours hours. You can rub the coat down after 24 hours with 0000 bronze wool (not steel wool) if you want. If you use steel wool, it is possible that small pieces of the metal will break off and become embedded in the wood and then much later when the stock is exposed to moisture they will rust and you will get rust stains in the wood.
Have fun!