A Montgomery County grand jury yesterday declined to take action against four county policemen involved in the shooting death of a 32-year-old Wheaton man who was fatally wounded by police on the doorstep of his home last Saturday.

After a presentation by the state's attorney office of evidence compiled by county detectives, the jury decided to close the book on the case which had drawn sharp criticism of the police action from relatives of the dead man.

Richard V. Williams was killed Saturday afternoon after he allegedly pointed a 22-caliber rifle at two officers and threatened to kill them.

Police had been called to a scene by a man they later identified as Williams, who reported a "man with a gun."

Pointing a rifle, Williams ordered the two officers who responded to drop their service revolvers and lie prone in the patchy grass on the side of his house in the 3400 block of Embry Street.

Police said Williams stepped toward the two officers, pointed the gun and said, I'm going blow your m . . . f . . . ass away!' He was shot in the left side by officers Ted Parker and William S. Issacs who crouched behind their cruisers 60 feet away in the street.

Because of inaccurate information put out by the police department, which first reported that Williams had been shot in the chest after pointing his rifle at Parker and Issacs in the street, the shooting was criticized by relatives who claimed the officers made no attempt to disarm Williams before killing him.

Earlier this week, police chief Bernard D. Crooke took the unusual step of declaring that the shooting was justified before the grand jury had reviewed the case. At a press conference in Gaithersburg, Crooke said that the officers were "legally, morally, and administratively 100 percent correct.They had an instant to act and they made the right decision."

The county's internal affairs section is still investigating the incident, but the four policemen, who had been placed on administrative leave, have returned to duty.