Nice post Francis. While I have owned at least one M12 between 1981 and October 2016 (I expect it will be a short absence from my gun safe) I have never had an M12 completely submerged. I have done it several times with my late 1970's 870 Wingmaster.
Pulled it out of the water, took out the shells, allowed the water to drain from action and magazine tubes, went back to hunting. Get back to camp at the end of the day, spray some hoppes #9 into the action and other spots, work the action a few times to spread it around and wiped the whole gun down. Works better today than when I received it 37 years ago.
I save my obsessing for my SxS's and my 98% M12 16 gauge.
