Yea I tried something similar the other day, they came out so ugly I did a second coat of the flat black to cover it all up.
As for the skittles colors and all, if they won't shoot in a little ragged hole at 25 or further yards and hold together after impact, I don't have a lot of use for them. Granted most of what I have shot of late has been all paper, or plastic filled with dirt, but one of these days those hogs are going to mess up, and I will find out exactly what they do, colored or not.