I have some old 60's era semi autos that were my fathers. Win 100 and a Remington 742. I do not think either of these guns have ever had any copper remover in them.
I am hesitant about using wipeout as it could enter the gas system. Just thought about using sweets.
Curious if anyone has experience with foam cleaner in a gun with gas ports?

EZ

I can't speak to commercial Remingtons, but I have used Wipe-out in my Garands, my M1 carbine, and my AR without any problems.

Ditto what Frank said. The product info clearly states it is safe for fairly prolonged exposure. I would not assume all Cu++-removing alkali cleaning products are NH3+ free, but the WipeOut/PatchOut products fall in this class. I leave the stuff in my uppers for days at a time. When all done removing copper I hit them with a CLP patch.

I've always heard not to use it in gas because it can't be readily neutralized.

I have a can of Gun Slick foaming bore cleaner on my shelf. It works well. It will set up and plug the gas block in an A.R. I know this from experience. I showed up at the range with a single shot A.R. until I found a pipe cleaner and unplugged the hole. Other than that the product works very well.