Free: Contests & Raffles.
Here's a handy chart: http://www.shotgunsportsmagazine.com/downloads/shotgun_statistics.pdfI think 250 to 300 yards would be the extreme distance that a #4 pellet could travel.I'm not aware of any statewide restriction that limits the distance from a structure within which a firearm cannot be discharged. There may be local ordinances, or other restrictions such as within wilderness areas, etc.Common sense and courtesy suggests that raining pellets of any size, under any conditions, is not conducive to enhanced property owner relations.
This acutally really surprises me for how regulated the state of Washington is on all things hunting. But, as H20 stated there is no requirement for shooting near buildings. I know in other states I have hunted there was requirements for not discharging firearms within 400 yards of inhabitated structures and not within 75 yds or maintained roadways. Here is seems like all is good as long as you are not shooting across or along a maintained highway.
I think the key is to video tape this *censored* and nail him to the wall with the hunter harrassment law. If no video at least audio tape him in his tirade tthen take some pics of your location.