I had not planned to build another gun, but bought a pistol barrel here that was for sale cheap. I finally got the stock finished and, using the same nitric and iron stain that has successfully been used on at least a dozen rifles, I went at it. It came out a very striking olive green, but I had seen this before. My electric heat gun, this time, did not convince it to turn brown. I tried again, but no success. I toasted the stock until it began to burn. No dice. Why did this happen, and how do I fix it? The Nitric acid originally came from TOW 20 years ago, and the stock us maple, likely red.