Hi Acer and Taylor,
The very best color that I ever achieved with maple was first staining it with nitric acid (not aqua fortis-no iron was in the acid) and heating. That turned the wood a blushing pink. After neutralizing the acid I then used water-based aniline dyes for the brown overtones. I built several guns years ago using that formula, all with good success but of course they varied somewhat depending on the wood. The best match I can find in my books are the colored photos of fowlers BS-12 and BS-14 in Grinslade's book. Those photos show color very close to what I achieved. I can no longer get nitric acid easily because everything here is flown in and shipping by barge is expensive for a small package. I don't like aqua fortis because in my experiments the color shows figure but it is the same brown color just in different shades. I want depth and variation in color, not monotonic shades of the same thing. On the best coloring job I ever did, I used the nitric acid, a wash of yellow aniline dye, and then brown dyes on top. The color was a mile deep and shimmered like cat's eyes. Unfortunately, it wasn't a muzzleloader. It was a maple stock for a Winchester model 75 which I built up for my first biathalon rifle. I eventually sold it so I could buy an Anschutz. I think the race officials used to take time off my skiing just because they liked looking at the gun so much.
Again Tom, you created a wonderful example of decorative art and displayed a deep understanding of styles and history. My hat is off to you.
dave