"We're up 500 percent," said Gabriel Vaughn.
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Vaughn owns Sportsman's Arms in Petaluma and says the new law is redundant.
"The state already requires a safety card to purchase a weapon, then a background check, and now another to purchase ammunition? All we'll get from this is a black market. People buying ammunition out of state and bringing it in. You can't track bullets."
On Tuesday, Governor Gavin Newsom hailed this enactment of Proposition 63 (passed in 2016), as a measure that will save lives.
"From San Bernardino to Ventura to Poway, too many Californians have already died from gun violence," he said. "I championed Prop. 63 because it is beyond the time that we take common sense actions such as these to keep deadly ammo out of the wrong hands and protect our communities."
There is a wrinkle, say owners of gun shops. While the law takes effect on Monday, they tell us they have received no directives from the state about how to enforce it.
"We're in the dark," said Vaughn. "I suppose we'll figure it out on Monday."