I tried it out 4 nights ago. Very dark black, no blue. Wear gloves, as bottle says as it does burn a little if in a cut, had a pinhole in 1 glove. When finished, washed off with warm water in shower. Finish is not bad, not very deep, scratches off easy. Going to clean barrel again on lathe and try again. Hopping for better results. It did a good job on the touch ups I did on the reciever & screws.
George