An article yesterday on the search for escaped murderer Bernard Welch incorrectly reported the number of handguns in the United States. There are 200 million firearms, of which 35 million to 40 million are handguns, according to a National Rifle Association estimate. Spokesman Dot Hester of the Bureau of Alcohol, Tobacco and Firearms said no figures are available for the number of firearms or handguns in the country. Hester said 71.8 million firearms and 28.4 million handguns were produced from 1970 to 1984.

Very soon and with great stealth, escaped murderer Bernard Charles Welch is expected to emerge from hiding.

Perhaps tonight.

Hunting with immense care and concentration, he could easily seize what he most needs: a new identity, a gun, money.

An unsuspecting traveler, a tipsy bar patron, an absent homeowner: A driver's license could come from almost anyone. Once in hand, it would be short, safe work to produce a new license with the original owner's name but Welch's photo laminated in place. Police call this a "true identity." Welch has had 10 known aliases in three decades of crime.

Next, the pistol.

In a nation of 200 million handguns, it would not be difficult for the man convicted of killing Washington cardiologist Michael Halberstam 4 1/2 years ago to arm himself. If he cannot buy a gun from a pawn shop or a street-corner hustler, no questions asked, he could steal one. The pistol he used to shoot Halberstam belonged to an FBI man whose house had been burglarized.

Then, the cash.

It was buried years ago, far from any city. To get there, he could steal a car or hitch a ride with an unsuspecting motorist or trucker. Once near the spot, Welch can trek for miles in thick forest. An accomplished woodsman and hunter since his youth in upstate New York, he would have little trouble finding his way.

This picture of Welch's likely moves as a fugitive emerges from more than a dozen interviews in recent days with police investigators, U.S. marshals, attorneys and officials in the Justice Department and other agencies involved in the search for the 45-year-old fugitive.

Washington area police, who blame Welch for thousands of burglaries and at least four rapes between 1975 and 1980, regard him as a master criminal who plans far ahead, bides his time, then strikes swiftly and unexpectedly. As he did last week.

Using the noise of a fierce thunderstorm to mask their effort, Welch and another convicted killer broke out of the maximum security sixth-floor of an "escape-proof" high-rise federal prison here May 14 by battering through a concrete wall with a weight-lifting barbell pipe, and sliding 75 feet down a floor-buffing machine's thick extension cord.

Although an emergency task force of about 30 U.S. marshals at the service's headquarters in Tysons Corners, Va., has received more than 100 telephoned tips and alleged sightings, Welch and Hugh T. Columb, a Vermont bank robber who knifed a fellow inmate to death six years ago, have vanished.

Headed by Howard Safir and Thomas Kupferer Jr., veteran investigators who helped track down "The Falcon," convicted spy Christopher John Boyce, the marshals' task force is trying "to think like Welch thinks, react as he reacts," Safir said. "Hopefully, this will bring us to him."

The marshals are closed-mouthed about how they are hunting for Welch. They face a formidable task. Officials call Welch "ruthless, confident, extremely intelligent, careful."

Sol Z. Rosen, Welch's D.C. Superior Court defense lawyer in the 1981 murder trial, recalled Welch as "the most intelligent, articulate, interesting defendant I ever represented. He was fascinating! He's very cold, calculating and immoral. He doesn't care who he hurts or how or what he does. What do you call someone like that? A sociopath."

Welch "is a brazen, practiced criminal, aware of many aspects of law enforcement," said Kupferer, U.S. marshal chief inspector.

"He knows about patrol observation and similar matters. As a burglar, he is among the most dangerous criminals, willing to go into another's house and risk confrontations."

Born in 1940 into a troubled Rochester, N.Y., family, Welch was -- and by all accounts is -- a loner.

"He confides in no one," said Montgomery Police Cpl. James King, who questioned Welch for hours after his arrest.

"He has no friends, no acquaintances, does not hang out with criminals. Talking to him about his crimes was like trying to make a butcher feel guilty about killing a steer."

First arrested in 1965 for burglaries, Welch spent 12 of the next 20 years in prison.

His longest stretch of freedom was six years, beginning in 1974 when he escaped from Dannemora prison in New York.

After stints in Richmond and Charlottesville, Welch bought an expensive house in Great Falls, Va., had three children by a common-law wife, Linda Susan Hamilton; bought a $39,000 silver Mercedes and a $235,000 summer home in Duluth, Minn., and opened a $1 million stocks investment account.

Burglary supported his personal empire. Police linked him to about 3,000 break-ins, many in Montgomery and Fairfax counties and Northwest Washington.

King said Welch was the unknown "Standard-Time Burglar," whose break-ins ceased when summer brought daylight savings time, or the "Standard-Time Rapist," because several women had been raped by a masked burglar.

"We figured he was summering somewhere," King said. "We were right -- he was in Duluth."

It all ended Dec. 5, 1980, when Halberstam and his wife, Elliott Jones, surprised Welch in their Northwest Washington home. Halberstam was shot in the chest. Driving to the hospital, he spotted Welch fleeing on foot, rammed him with his car, then collapsed and died.

Later, in a Life magazine jailhouse interview, Welch complained that Halberstam "ruined my life." Welch boastfully described melting stolen silver and gold antiques in his basement smelters and selling ingots in Minnesota.

The houses, cars, stocks and valuables were seized by authorities, returned to victims or sold for back taxes. About half the stolen goods remain in police custody, unclaimed. Hundreds of burglary cases are still open, because prosecutors would not grant Welch immunity from self-incrimination.

The rape cases remain open, but King accuses Welch on the basis of what victims told him. "No body odor, no tobacco smell, upper and lower false teeth, a full set. I called Dannemora -- they said it was Welch."

Although he never married Hamilton, Welch telephoned her often from prison, Fairfax Investigator Donald Neese said. "He was interested in the kids." Hamilton, a Duluth woman who lives in the Washington area, "would like to just be left alone to work out her life," Neese said. "He used her. She hopes he's not coming back . . . . "

Most officials say they think that Welch will go to some other part of the country, perhaps southern California, and return to his old ways: careful neighborhood surveillance, approach after dark, cut the telephone line, jimmy a window or door, make off with "only the very best pieces."

"He's five years older . . . . Is he going to get back into it?" mused Tom Bailey, a Fairfax investigator temporarily assigned to the marshals' task force. "Just how much desire does he have? How much money has he stashed? If he doesn't have any, he'll start breaking in anywhere."

Jay B. Stephens, a senior Justice Department official who, as an assistant U.S. attorney, prosecuted Welch and obtained a 143-year sentence, said special precautions were taken to send Welch to "the most secure prison in the U.S." -- the maximum security federal prison in downstate Marion, Ill. But Welch was transferred to the Metropolitan Correctional Center here, from which he escaped.

"My assumption, belief and intent was that he remain in Marion because of his history and conduct," Stephens said. "Because he was sentenced to serve the rest of his life in prison and his only hope of getting out was to escape -- and he himself said he would escape -- we deliberately requested he be sent there. I have a professional and a personal interest in Welch's capture."

Arlington County, Va., Detective Cecil Arnold, deemed by many of his colleagues as a specialist on Welch, said, "I would assume he'd do the same thing all over. He knows antiques. He'll steal good pieces, not museum quality, a nonserialized item. But valuable. Store them up, take them to a dealer a long way away. Make money that way."

Perhaps tomorrow