“It is really far-reaching and bold, and really has the potential to save a lot of lives,” Ms. Wilcox said. “It can give us a handle on who has illegal guns in the state, as well as limiting access to ammunition by dangerous people who may have illegal guns.”

The new laws would prohibit the possession of high-capacity magazines — those holding more than 10 rounds of ammunition — for assault weapons. “These so-called high-capacity magazines are not for target shooting or hunting,” said Senator Loni Hancock, a Democrat who sponsored the bill. “Their sole purpose is to kill as many people as possible in the shortest period of time.”

A separate bill banned semiautomatic weapons with “bullet buttons,” which make it easy to quickly remove a magazine and replace it with another.

Among the bills Mr. Brown vetoed was one that would have expanded the definition of a firearm. “While I appreciate the author’s intent, the actual wording of the bill is unduly vague and could have far-reaching and unintended consequences,” Mr. Brown wrote in his veto message.

Shannon Grove, a Republican Assembly member who spoke out against the bills during the debate, said that none of those signed would reduce gun violence or prevent mass shootings. Instead, she said, the restrictions compromised the rights of California families to protect themselves.

“I think it’s death by 1,000 paper cuts for our Second Amendment rights,” she said. “Nowhere in this nation do you give up your rights under any other amendments.”

The signing was not the end of gun control measures that might be enacted here in the wake of a wave of violence that has traumatized the world and the nation, including the shooting in San Bernardino that killed 14 people at a holiday party in December. A separate set of gun control measures will appear before voters in November; some of them have been passed by the Legislature, but Mr. Brown vetoed those, saying they should be left to voters to decide.