I have changed over to using Tung Oil on my rough use hunting guns. It penetrates deeply and seals very well. The only problem with Tung Oil when used by itself doesn't fill pores well even when sanded in so taking a hint from one of SDH's tutorials on stock finishing I mix in a bit of Rottenstone to fill the pores. It takes a bit longer but you end up with one tough finish that is very moisture resistant and looks nice.