just yesterday used the FeNO3 crystals mixed with denatured alcohol - my third effort with this brew and I like it.
I use 10ml crystals dissolved in 25 ml denatured alcohol, or 1 part FENO3 -to- 2.5 parts EtOH, by volume.
1st coat, let dry, then blush with heat gun, 2nd coat. dry, repeat blush.
after its dry, I do rub the wood down lightly with a rag dipped in ammonia to neutralize - don't really know it helps or not.
gave a nice rich brown on this particular piece of wood - if one wanted more red tones, might have to overlay with a favorite stain.
For the second coat, I applied as per a Jim Kibler tip on this forum
http://americanlongrifles.org/forum/index.php?topic=17969.msg168720#msg168720: with a scotchbrite pad ( I used green, Jim suggested maroon), scrubbed fairly firmly.
I had not raised the grain or whiskered previously, and this gave a nice smooth result.
Will seal and burnish soon, as per Jim's narrative.
/Mike M