I put a BSA low end red dot on a plinker a few years ago. When I got it out yesterday to switch it to a pistol I noticed that it was sticky all over. I used my fingernail on the surface and the finish scraped off. Next I wiped it with alcohol and the finish came right off. It was very black on the rags and cotton swabs but underneath, the aluminum tube was anodized black. So, it looked the same but I was clearly removing some sort of rubbery finish coat. I took me about 40 minutes to get most of it off.
Any ideas about this gunk?

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searoom

That was the same with an BSA air rifle scope I own.When I tried to clean it a kind of rubbery finish started to peel off.I then removed it completely.
Regards, Ray

Might be water proofing gone bad. Don

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