Does water get into the gastube or does having the barrel capped and bolt closed good enough?
This is a subject with that has seen no coverage here so any info you want to add would be like gold.
I usually never cap my barrel with anything unless its a bfa (Blank firing apparatus). Not that barrel caps are bad, its just that I forget that there on and shoot through them or I leave them on for extended periods of time and cant get the darn thing off (I'm then forced to shoot it off anyway
). As for water, nothing keeps it out unless waterproofed inside a container or bag. Just make sure you point the barrel to the deck BEFORE exiting the water. As you pull the rifle out of the water, barrel down, it acts like a straw being pulled out of a glass of water , the water level in the barrel and gas tube are equal to the ambient environment, as the barrel comes out, the water stays where it came from. End result: Empty gas tube, barrel, buffer tube, and everything else. If you wait to "dump" the water out of the barrel, not all the water may come out of the gas tube and could possibly blow the gas tube or piston at the gas port in the barrel due to over pressure .