Most of the nearly 3,000 weapons exchanged for a $100 bill during this summer's gun amnesty program were about 15 years old, many were cheap revolvers barely worth $30 on the street, and none of the ones tested so far had been used to kill anyone, according to an analysis by the Bureau of Alcohol, Tobacco and Firearms.

The study represents the first comprehensive look at the weapons turned in by citizens in these "buyback programs," used by many police departments to remove guns from the street.

But while the study appears to validate one frequent criticism of such programs--that the weapons turned in are often old or inoperable or both--District police officials nevertheless called their largest-ever weapons harvest a success on several fronts.

"If it results in one case closed, if one person is put in jail or if one death is prevented, then it was worth the money," said Assistant Chief Brian Jordan. "You can't predict when a gun will be used in a crime."

Seven days' worth of collecting and three months of analysis gave investigators a perspective on what types of weapons are in the District.

According to the report, 44 percent of the guns in the buyback were traced to regional gun shops. Virginia, Maryland and Florida provided the largest numbers of weapons. Some came from California, Texas and even Alaska.

When District police stations opened their doors in August, offering $100--from seized drug profits--in exchange for a weapon, Jordan said most of those wanting to get rid of these guns were senior citizens. Among the weapons turned in were six Daisy air rifles and one hand grenade. Some brought old guns wrapped in tea towels. One person turned in a $3,000 collector's classic, he said.

"We take guns off the street in many ways. This is one way," he said.

Buyback programs--popularized nationwide this decade and offering such tokens as sports tickets, teddy bears, sewing machines and gift certificates in exchange for weapons--are often called a quick fix with little impact on violence.

"Gun buybacks are kind of a hit-and-run approach to gun violence," said Josh Sugarmann, executive director of the Violence Policy Center.

"I think gun violence seems too intangible to people. At the end of the day in these gun buyback programs, there's a tangible result--the guns. That makes people feel good."

But some question whether that good feeling is worth $300,000.

Jon Vernick, associate director of the Johns Hopkins Center for Gun Policy and Research, suggests money can be used to move higher in the gun trade hierarchy, targeting gun traffickers and straw dealers.

Jordan said such programs and the data they provide are building blocks to other phases of weapons seizures.

Each of the 2,912 guns netted in Operation Gun Tip was analyzed for its origin and history. Because the District analyzes all weapons and it was one of the target cities in a recent ATF gun study, the climate was right for such a unique analysis, said Brad Earman, spokesman for the ATF.

According to the study, many of the weapons were manufactured before the 1968 Gun Control Act and didn't have the serial numbers that allow the guns to be traced.

Some, 68, had their serial numbers obliterated, a sign they had most likely been stolen. There were 45 guns that had been reported stolen from 17 states, a fact that Earman said proves buyback programs help target crimes, even if they're not helping solve homicides.

Other criticisms are aimed at the kinds of guns turned in. During the 1994 gun amnesty program, only 56 percent of the weapons were handguns. That increased to 75 percent this year, according to the report.

More than half of all those guns, however, were revolvers.

"That doesn't comport with the majority of the crime guns out there," Vernick said.

Some of the guns turned in are on the ATF's most dangerous list, such as the Raven .25-caliber pistol and the Davis .380 pistol. Few were high-powered semiautomatics.

"Someone isn't going to be turning in $400 weapons, we know that," Jordan said. "But we are preventing guns from getting in the hands of children."