For what it is worth.
I do not think that water, plain water, will harm the wood.
The Portsmouth Navy Shipyard has quite a few huge timbers, submerged in a lake, to be used as needed to restore any wood on the USS Constitution.Most of these timbers are white pine and were cut in the 19th century. They are as sound as when cut.
It seems, to me, that being under water would not have greatly harmed the wood on any gun. Metal is another thing.
I would think that any salt could be easily "washed" out with soaking in fresh water. The residual oils in the walnut should have protected the wood for a long time.
This is NOT the same scenario as the wood that was used on the Browning guns.
Best,
John
