I don't own a gun, but I have had fantasies about doing exactly the same thing. Vigilante justice is an American tradition. A better course of action probably would have been to photograph the drone and report the incident to law enforcement.

What's law enforcement going to do about a photo of an unmarked drone? This is only useful when the drone can be traced to its owner.

There's an interesting comparison here to the advent of airplanes. Lawrence Lessig goes into it a bit in Free Culture but the basic gist is that when you owned land and a house, you owned the land "up to God." Then airplanes came around and suddenly you didn't actually own all the area above your house, just a portion (relatively) near it. In large cities, you can even "sell" the air rights, so fancy buildings will buy the top whatever "floors" of neighboring buildings to keep them low and allow fancy tenants to keep their nice views.

I do not have a problem with this.

Neither did some of the local law enforcement:

  "The 43-year-old man claimed that law enforcement officials, 
  including the county jailer, told him privately that they 
  agreed with his actions."