JW
I have used epoxy in various formulations for boatbuilding work. It is well suited to applications demanding water resistance. I have no doubt Jay was impressed with his results, but question whether thinning an epoxy adhesive with acetone can create a sealant/finish that might be better than a epoxy product specifically formulated as a sealant/finish.
Some epoxy laminating resins are, by design, quite thin and well suited for your intended purpose. I use System 3 clear coat in applications similar to yours. I find warming the wood to 120* F prior to application of the resin significantly helps with penetration.
My preference for system 3 is only because it is available locally. West systems also has formulations with similar viscosities which I would presume to work equally well. These thinner formulations can also be thickened for usages that call for more viscosity.
When limiting my choices to a natural finish, I agree with Mike
A well done tung oil finish is as resistant as anything
On wet weather hunts here in Alaska, I keep a small tin of beeswax mix,( thinned into a firm paste with some oil), for frequent application as needed.
Dean Torges did some experiments published in one of his books which showed a wax finish to be most effective for his purposes also.