A special D.C. police task force, set up 16 months ago to "stop traffic in pot, powder and pills," has made more than 4,000 narcotics-related arrests and, according to task force detectives, significantly curbed street drug dealing in the nation's capital.

The task force says that it also has confiscated 114 handguns, 13 shotguns, three rifles, 13 cars, two vans, a motorcycle, $175,000 in cash and a variety of drugs, including heroin, cocaine and marijuana.

The team often relies on a controversial tactic known as "rip teams," or "jump-out squads." An undercover officer finds out who is selling drugs in a street crowd, then signals a squad of three to five policemen who approach in an unmarked car, jump out and arrest the startled suspect.

Those connected with the campaign do not claim to have had a major impact on the overall drug trade in Washington, but rather to have cut down on its most visible manifestation: the street-corner traffic.

"A year ago, you could buy drugs on any number of street corners: l4th and U, Seventh and T, Martin Luther King Avenue and Talbert Street SE. Now you can't," says Sgt. John Brennan, a member of the task force.

Police Chief Maurice T. Turner, who is considering making the experimental unit a permanent part of the department's narcotics enforcement branch, said that he is pleased with the results so far.

"When I took over as chief I thought we needed a more active program against street dealers," Turner said. "People were hawking all kinds of drugs out in the open, an obvious detriment to the quality of life in the city. I think our unit has had a tremendous impact on reducing that."

No figures were available on how many convictions have resulted from the squad's arrests.

Community leaders around the city generally applaud the 34-member task force for making the streets visibly cleaner, although some residents have complained that the sight of policemen in such zealous action frightens them.

"We had a community meeting and decided to call in the 'jump-out boys' to clean up this alley where junkies hang out," said Eugenia Jackson, a tenant at the Kenilworth Courts public housing project in far Northeast. "We told them they could use whatever force was necessary to clean up the problem, but now I'm afraid that some innocent bystanders will get jammed up, because those guys play rough."

The unit's efforts have had other effects that could affect Turner's final decision. For instance, some prosecutors in the major crimes division of the U.S. Attorney's office, which is down from l7 prosecutors a year ago to l0 now, have complained that the increase in caseloads bogs down the system with "small-time" drug peddlers.

Furthermore, the prosecutors say, the task force's "jump-out" tactics are more suitable for proving possession of heroin, which is a misdemeanor, as opposed to proving intent to distribute the drug, which is a felony.

The result is that those suspects whose cases go to court frequently are convicted on charges for which they spend little or no time in jail.

"These guys are pumped up and they are doing a damn good job, but we have to pick our cases and be concerned that we don't get so many that nothing happens," said Assistant U.S. Attorney Donald Campbell.

"I understand their frustrations," said Campbell. "You see a guy you know is dealing drugs, but knowing something and being able to bring into court evidence to prove it are two different things. That's the rub."

The task force is composed mostly of young officers from the seven police district stations, organized into squads that operate city-wide. Motivated by the desire for a permanent assignment in the prestigious downtown narcotics squad, as well as overtime pay, they work long days and have earned a reputation for being gung-ho.

Members of the task force say they are undaunted. "All you can do is your job, which is to arrest people," said Officer Peter Serbinoff, a task-force member. "Most of the guys we arrest are charged with felonies, but few are arraigned as felons and fewer are convicted as such. Sometimes you arrest the same guy seven, eight times."