Yes, that really looks like what I have referred to in other contributions as a "treacle rifle":
Modern jelly-type paint stripper - the stuff that burns your skin (I think it contains some kind of -uol or -ene -toloul? xylene? who knows?) - will remove just about anything - apart from original Urushi lacquer! As others have said, you have nothing to lose.
BUT - you do NOT need to use sandpaper or wire wool. Sorry, let me correct that: NEVER use sandpaper or wire wool. I have described how to do it some detail in a long series about restoring an
Argentine Rolling block. I suggest you look it up.
Forum/Milsurps Discussion Forums/The Restorer's Corner /Argentino M1879 Rolling Block. Is it worth restoring?
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