No kind of skill or secret to share, but I used black paint once. A Mike Brooks posting here inspired me to try it. I did not spray it on but I rubbed it on with a rag after the last whiskering. I rubbed it back vigorously, in fear mostly (lol)--- it made the walnut stock look like a black and white photo. It scared me to death actually. I then applied the finish and wow. it really looked great. The black went into the grain and the final result was very warm, rich and old.