I used mink oil (made by Kiwi, in the shoe polish type can) on my hunting bow last year. Got caught in th rain once, the water beaded up an ran off. For those of you that don't know, Mink Oil is a leather waterproofer and conditioner. It is made from a combination of mink oil, silicone and lanolin, and it seems to work well as a finish for bows as well as leather. Just apply it as you would any other type of grease or fat.
Dale.