Best advice is make sure it is clean, guns have grease and oils... I always clean mine with brake cleaner and then bake it for 5 or 6 min at 300 or so degrees.that will pull any oils out of places they hide and i then clean it again. after i clean it the second time i paint it while the metal is still warm and I do a light coat and let it sit in the warm oven (my oven cools really quick) usually about 100-125 degrees for 15 min and then I cook at 350 for 15 min.. I kill the heat and leave in the oven with the fan blowing in it until i can touch the action. I only duracoat the actions, everything else I Krylon so i can change and touch up as needed. Multi color duracoat like my brush camo action are tricky, I do the base color and cook for 5 min and then pull and spray, over and over again, only cooking for a couple min between coats.