After reading therealrasta's post (#10, above) I followed the link and did a little reading. They offered some believable advice, specific to gun sights.
http://glowinc.com/glow-in-the-dark/gun-sights.aspx
For what it's worth, I too think you would be far better off with tritium sights. If you're determined to settle for "do it yourself" paint, this stuff might be worth a try.