It's Mayor Tony Spitaleri's measure.
"Schools having violence with, involving guns and people being killed. It's almost like we're getting numb to this thing. It's like become a way of life," he said.
The ballot measure will require reporting thefts of firearms within 48 hours, gun owners will have to lock up their weapons, gun dealers will have to keep records of all ammo sales and owning magazines with more than 10 rounds would be illegal.
Spitaleri was inspired by Mayors Against Illegal Guns, a group founded by New York Mayor Michael Bloomberg, who contributed $3,000 dollars to Measure C.
"We can't get anything done through Congress. We can't get anything really done on the state level. And we can't wait for top down. It has to come from bottom up," said Spitaleri.
The mayor says he's gotten a lot of support for his measure. But there are critics as well. Eric Fischer owns U.S. Firearms Co. in Sunnyvale. He feels the measure is poorly drafted and is an attack on legitimate gun sellers and owners.
"It's just designed to drive business out of Sunnyvale because you can buy ammunition anywhere else in any other city without the same requirements. So, the only effect it's going to have is to drive sales out of my shop and into neighboring cities," said Fischer.
Gun owner Peter Leach owns a 15 round magazine, which is legal under state law because he bought it before 2000. If Measure C passes, he's afraid it'll make him a criminal.
"They're going to come arrest me the minute the law gets passed. Or, you know, if I'm driving to turn them in, am I going to get caught for that right there?" he asked.
The National Rifle Association says it will sue if the measure passes, saying, in part:
"The city of Sunnyvale is attempting to overstep local government authority and intrude into an area regulated by the state."