There is no Castle Doctrine in any state that provide's fpr arming yourself then leaving the safty of your house to sneek up and tap the window of a parked car with a loaded gun.
If the people in that car had been armed and a gunfight insued,they would have stronger claim to stand your ground than you would. Guaranteed you would face a grand jury that would have no choice but hand down an indictment since you intentionally pursued them with a gun. The prosecuter would claim you clearly wanted to kill someone otherwise you would have stayed in your house. Your claim of only wanting to frighten them away would'nt sound true since you sneeked through trees instead of walking down the road in plain sight.
They would say you sneeked through the trees so that you would be in gun range when they finally saw you.
People to which "word got around to"would witness your fondness for waving a gun around and appearant desire to shoot someone. If you ever face a problem involving firearms,what you say on public forums like this could be driving nails in your cell door.