Yes, it will work fine on your blued guns. I believe that it does have a very slight abrasive in it, so I would not go too crazy, but it works well to shine up the blue (and nickel...).
After seeing the replies on Flitz in this forum, I tried Happich Simichrome on an old 32 DA that had a lot of surface rust.
It worked fine on the rust w/o going thru the blue. It has a
very fine abrasive in it, like the Flitz.
TACC1