Is it the kind of metal used? Seems to be an issue for crosman guns, or maybe more likely to be hand pumped without any moisture control?
Strange.
I’ve seen it on multiple metals...it will damage your gun’s valve and bore the most, but it does eventually mess with your gun’s cylinder. The problem too is that the moisture’s cross pollution of rust and moisture deposits (they are hard crystal like substances, most of the time white but sometimes a milieu of other colors based on the input device, and of course the white goop identified by the Original Poster) that gets carried first in to your cylinder and then off to your valve and barrel. Now here is the crazy thing, most hygroscopic substances we use have a caustic nature when in contact with various metals, including aluminum and stainless steel, effecting a compromise on the structural integrity of the tank. I have never seen a tank fail, or heard of it even, but the science is there and the evidence abounds as to what occurs with the Introduction of moisture, and even with dry packs and filters of various kinds you are fighting a battle not winning a war, if that makes sense. This topic is rather repeated a lot here if you click search, and there are many posts about gun damage like the above accessible through that function. Just use common sense and try your best is all. I have a HillMk4 that I just bought for backpacking so I am in the process of finding the highest quality filter I can afford, and it is hard a hard process especially when looking at the quality of the alpha filter.
So take of you air or you will suffer the same thing
