Thats the theory burning powder produces water, ammonia, and other bits not enough to cause a river but enough to make a humid environment.
The ammonia will prevent the barrel from rusting (rust wont form in an alkaline environment) but its not good for aluminum or duralum supressors and you could see white spots developing on the inside of the supressor if you can disassemble it.
Solutions lesving it on the rifle
1/ shoot till the supressors so hot you burn your hand leave it muzzle up breech open till cold. Then store.
2/ put it in the hot water cupboard to warm up breech open before putting it away
3/ there is no 3
4/ dont bother about it
5/ fire some crc into it
I personally am of the 2 and 4 school. Constantly winding it off and on is a pita and over time with duralum flogs the thread a bit especially on 1/2 x 28 and a loose supressor is bad.
I do take it off occasionally when i feel the need to clean the bore as using a rod or boresnake through a can has been known to have unforseen complications.
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