In a buyback event held Saturday, the final tally shows that 680 guns—including 24 assault weapons—were turned in at the San Mateo Event Center, said Detective Rebecca Rosenblatt, a San Mateo County sheriff's spokeswoman.
In addition to the assault weapons, 371 long guns and 285 handguns were turned over to officials, Rosenblatt said.
In exchange for the guns, officials paid up to $100 in cash for a handgun, shotgun or rifle, and up to $200 for an assault weapon.
"It was such an awesome turnout that by the end of it we had essentially a pile of guns," Rosenblatt said.
"I would say it was a hugely successful event," she said.
The event, sponsored by San Mateo County Sheriff Greg Munks, San Mateo County Supervisor Adrienne Tissier and U.S. Rep. Jackie Speier, paid out more than $63,000 in cash in exchange for the guns, officials said.
"The success of the gun buyback exceeded our expectations," Speier, a Democrat who represents San Mateo and the surrounding area, said in a statement.
"People are moved to get rid of guns they no longer need or want. Every weapon turned in is one less life that might be lost or damaged by a firearm, whether accidentally or intentionally," the statement said.
The buyback was scheduled to start at 10 a.m. Saturday, but with cars already waiting in line for blocks outside the event center, officials opened the gates early.
Officials planned on destroying the guns collected, unless they had been used in a crime of if they were stolen, Rosenblatt said.
"If we determine any of the guns were lost or stolen, we would do our best to get them back to the rightful owners," Rosenblatt said.
The San Mateo County buyback comes after hundreds of guns were turned over for cash in recent buyback offers in Marin County, San Francisco and Oakland.
Earlier this month, a buyback offer in Marin County was so overwhelmed by people selling their firearms that officials ran out of money. After collecting 827 guns, the Marin County district attorney's office doled out $43,000 for the guns and distributed another $40,000 in vouchers.
In December, about 600 guns were turned during over to authorities during a buyback in San Francisco and Oakland.