Just after midnight on Nov. 23, 1979, four young men looking for guns climbed up a fire escape at the National Rifle Association annex building on 16th Street NW. They removed a metal grill that covered an open window, slipped inside and began their search for weapons. Three hours later, they had stuffed a briefcase with their loot: four antique pistols, a flare gun, a stop watch, some postage stamps, and a .22 caliber Supermatic semiautomatic pistol and ammunition.

Four days later, attorney James E. Rooks Jr. told a U.S. District Court jury last week, a robbery took place at the corner of 17th and T streets NW. One of the holdup men, Joseph (JoeJoe) Nix, had been involved in the NRA burglary and the other, John H. Hart, was armed with the stolen Supermatic -- loaded with a single bullet. A fight began when the victims resisted, and Nix wrestled with one of them, Orlando Gonzales-Angel.

"Shoot him! Shoot him!" Nix shouted to Hart, a prosecutor later recalled. Hart fired the gun. The single bullet struck Gonzales, 28, in the back and pierced his heart.

"There was nothing that could be done to save his life," said Rooks. Gonzales, an animal caretaker at the National Institutes of Health, died that day at the Washington Hospital Center. Nix and Hart later were convicted of murder in connection with his death.

Now Gonzales' family has filed a $2.5 million lawsuit against the NRA and the owner of the Supermatic pistol, a now-retired employe and champion marksman who used the gun during lunchtime target practice at the NRA pistol range.

The family's claim, which the jury must decide, is that the alleged negligence of the NRA -- the nation's foremost proponent of private gun ownership -- and its employe caused Gonzales to be murdered by a robber armed with a stolen gun.

"We are not here to harass anyone or to have revenge," Rooks told the jury at the opening of the trial last Friday. The family seeks $2 million in punitive damages against the NRA and $15,000 in punitive damages against the gun's owner, as well as $550,000 in compensatory damages. the cost of his funeral.

Rooks told the jury the evidence in the case will show that the NRA should have anticipated that its headquarters building would be a target for burglars seeking guns and should have taken safety precautions against break-ins. Moreover, the family contends, the NRA allowed its employes to bring guns to the building but provided no place to store them and no written rules about their use.

The lawsuit also alleges that the employe, Robert W. Lowe, of Silver Spring, violated basic safety procedures when he stored his weapon, which was unloaded but without a trigger lock, and ammunition in the same place. It contends that although Lowe had hidden his weapon in a trunk in a locked closet in his NRA office, he was negligent when he left the key in a nearby desk drawer, where it apparently was found by one of the burglars.

Edwin A. Sheridan, the defense lawyer for the NRA, told the jury Friday that the NRA allows "shooters" like Robert Lowe to bring their guns to work for target practice at the office shooting range but requires then to take the gun home at the end of the day. It was an unwritten policy, but it was nevertheless known by anyone who used the NRA range, Sheridan said.

NRA contends Lowe violated that policy, Sheridan told the jury, but they will not concede that Lowe was negligent or careless. Instead, the NRA will present expert testimony from a man identified by Sheridan as "the most prestigious shooter in the world today" who will state that Lowe acted responsibly because he had his weapon in its kit, unloaded and in his private office.

The NRA argues that it could not have foreseen the criminal acts that led to Gonzales' murder and thus could not have taken steps to prevent them. The association pointed out that four days passed between the burglary and the murder and that during that time, the murder weapon changed hands and ended up with John Hart, who had not participated in the NRA burglary.

Lowe, now 64, was director of the NRA gun collector's department when he retired in January 1980 after 20 years of employment there. He has a reputation as a "distinquished shooter," Sheridan told the jurors. When the burglars came upon Lowe's gun, Sheridan said, they found the only operable weapon in the NRA that night.

Lowe's lawyer, Randell Hunt Norton, agreed in his opening statement to the jury that Lowe sometimes left his gun at the NRA overnight and said his client had never been informed that such a practice was prohibited.

"He is a man who follows the rules," Norton said about his client, a veteran of the U.S. Marines and Army, who has been a competition marksman since he was 16 years old. Gonzales' death was a "tragic murder," Norton said, but "whatever Mr. Lowe did had absolutely nothing to do with [Gonzales'] unfortunate death" four days after the NRA burglary.

When the trial resumed yesterday, the jurors heard a sworn statement from Charles Fletcher, one of the youths convicted of the 1979 burglary at the NRA annex, in which he said he went to the NRA that night because he had been involved in a break-in seeking guns there a year earlier.

Fletcher, who has not been charged with the 1978 burglary that he described, said in the statement that he went to the NRA building in 1978 because his partner at the time believed it was likely that guns were stored in the NRA building. Attorneys for Gonzales' family contend that signs on the NRA building, which use words like "rifle," "arms" and "range," could lead some persons to think weapons were kept inside the building.