[Daves55Sedan]

Sometimes the valve in the top of the can gets stuck and won't allow the sprayer to go down. If it is just the spray nozzle, I keep a little box full of all kinds of spray nozzles and usually the replacement works in the can.
But even if it is the valve in the can, I still never waste the paint. I keep an empty quart paint can and have a roofing nail affixed to a metal base so the nail wont tip over. Set the nail pointing upward inside the quart can, turn the defective spray can upside down and put it down in the can so the top is against the nail. Hit the bottom of the spray can with a hammer and the paint spray comes out, but can't splatter all over the place because the hole in the can is way down at the bottom of the quart can.
Then I pour the paint into my little detail spray gun, fire up the compressor and go to town painting. I've never thrown away a can of paint because of a bad valve or nozzle.