Mass murderer Patrick Henry Sherrill was a painfully lonely man whose private life and public death were shaped in some measure by two obsessions: a love of guns and a fear that he might succumb to a debilitating mental illness like the one that struck his father.

That portrait of the vengeful part-time mail carrier emerged today as police investigators, postal officials, friends, families, ministers and psychologists searched for facts and understanding the day after Sherrill's rampage at the U.S. Post Office in Edmond, where he methodically shot and killed 14 colleagues and injured six more before turning a semiautomatic weapon to his head and taking his own life.

Postal workers unharmed by the shooting spree -- at least physically unharmed -- dealt with their grief and anger by returning to work and getting the mail out. They arrived at their posts at 1:15 this morning. The building had been cleaned and scrubbed, but a few blood stains remained: one near the work space of slain mail carrier Mike Rockne, grandson of the famed Notre Dame football coach Knute Rockne; another near the supervisor's desk where Sherrill killed himself.

Oklahoma County District Attorney Bob Macy revealed this afternoon that Sherrill, 44, a skilled marksman in the local Air National Guard, had borrowed the two .45-caliber pistols he used in the massacre from the guard unit, one in April and the other Aug. 10. Sherrill practiced his aim at a local shooting range last Saturday and Sunday, Macy said.

As a member of the guard unit's marksmanship team, with which he was to compete next Monday in a national tournament in Little Rock, Ark., Sherrill was allowed to check out guns and 200 rounds of ammunition whenever he desired.

Sherrill's fascination with guns went back at least as far as his service in the Marine Corps from 1964 to 1966. Janet Cox, an attorney who probated his mother's will in the late 1970s and had regular conversations with Sherrill thereafter, said that the one time she visited his small white house in northwest Oklahoma City he spent two hours showing her his gun collection.

"It was strange the way he did it. It was the one time I was frightened by him," Cox said. "The guns were all hidden. He took me into a bedroom and pulled one out from under his bed. Then in the kitchen, he pulled out a few from different cabinets."

When police searched Sherrill's house, they said today, they found a silencer and several pistols along with copies of Soviet Life and Soldiers of Fortune magazine. The remnants of scrambled eggs were still in a pan on the stove. There were no suicide notes or indications of the tragic mission upon which Sherrill embarked after his breakfast Wednesday morning.

In the days before his violent explosion, Sherrill had several run-ins with his supervisors at the post office.

On Tuesday, according to postal officials, he had been criticized for his lackluster performance and told that he had to improve if he wanted to keep his job and earn a promotion to full-time carrier, a position for which, by seniority, he was next in line.

According to Don Bradshaw, vice president of the American Postal Workers Union local, Sherrill had called him several times in recent months seeking a transfer to the maintenance shop in Oklahoma City. The last call came Tuesday afternoon, Bradshaw said, when Sherrill profanely complained that he was "sick of this expletive " in Edmond and implored the union to "get me out of this expletive mess." Bradshaw said union officials always told Sherrill the procedures for a transfer, but he never followed through.

Bradshaw and other postal workers interviewed today described Sherrill as a somewhat withdrawn individual who occasionally expressed great frustration but no more often than many other mail clerks and carriers. "I've run across some real kooks in this business," Bradshaw said, "guys who were always screaming and threatening to do just what Sherrill did. I never believed them. But I didn't expect this from Sherrill."

Sherrill's oldest and closest friend, Charlie Harris, now a minister and psychotherapist in Arlington, Tex., said Sherrill was a shy person whose loneliness seemed to result from an empty home life. Harris, who was in Sherrill's 1959 graduating class at Harding High School in Oklahoma City, recalled that he would sometimes talk in fatalistic terms about his father, Robert Sherrill, who is now believed deceased. At that time the elder Sherrill was divorced and lived in another city.

"I now remember vividly that Pat would tell me that his father had a disabling mental illness," Harris said in an interview today. "This was 25 years ago, and when I think about his descriptions now, it sounds like perhaps it was Alzheimer's disease. In any case, he would talk about it and say how he was afraid he would get it in middle age. I remember him saying that that was why he didn't want to get married or have children, because he didn't want to pass it on in his genes."

Police investigators have not yet discovered where or how the elder Sherrill may have died.

In high school, Harris said, Sherrill was on the periphery of the most popular group of kids. "We went to movies together and hung out at the Split-T Restaurant. No one disliked him. He had a dry sense of humor. If there was anything strange or negative about him, it was his lack of social skills. He was just shy and awkward, a big guy, about as big then as he was later, maybe 6 feet and 210 pounds. And he was balding even then."

Harris and Sherrill went to Oklahoma University after high school, but Harris lived in a fraternity and Sherrill in a dormitory.

"He never had much money in his life," Harris said. "That must have pulled him away from his peers to a certain degree. He couldn't afford to do certain things others of us could do."

Sherrill dropped out after one year. He spent the next two decades drifting from one temporary interest to another: the military, different colleges and universities and various jobs. "Every time I came back home and saw him he seemed more lonely and withdrawn," Harris said. "Maybe I should have reached out to him more. My job is to help people like him, but I guess because he was my friend it was actually harder. He had this wall. He made it clear that you could go so far, and no farther."

Attorney Cox said that in the last seven years she had spent countless hours talking with Sherrill but never got to know him.

"He was always friendly, but from the first time I met him I realized he was an extremely lonely person," Cox said.

"We'd talk about anything except his personal life. He was real pro-American, patriotic, and he liked to talk about marksmanship and about current events, especially the Middle East," Cox added. "But in the back of my mind I always thought he needed help. And when I heard about the shooting and heard the name Pat Sherrill, I thought there may be a lot of Pat Sherrills but it's got to be him. I don't think he could handle the loneliness."

Thirty ministers and city officials gathered this morning to coordinate the difficult healing process in Edmond.

They were joined later in the day by psychologists from the National Organization of Victim Assistance, including Michael Mantel, the community crisis coordinator in San Ysidro, Calif., after the slaying of 21 people at a McDonald's restaurant there in 1984.

Members of the Edmond clergy tried to make sure that families of the dead and wounded had as much spiritual and psychological help as could be provided.

They planned a community memorial service to be held Sunday afternoon. On the night of the shooting, the first memorial service was held at the First Baptist Church of Edmond. Three of the 14 killed by Sherrill had been members of the church.

After counseling the victims' families all day, Alan Day, the minister, stood before hundreds of grief-stricken parishioners and said this city would recover and learn from the tragedy.

Day ended his sermon with these words: "We clench our fists in the face of death and say, oh death, where is thy sting. Oh grave, where is thy victory."