SUNNYVALE -- A federal judge's last-minute refusal to put Sunnyvale's new gun-control ordinance on hold means that, as of Thursday, anyone in the city who possesses an ammunition magazine that can hold more than 10 rounds will be a criminal.

The National Rifle Association asked a federal appeals court Wednesday for an emergency stay, hours before the law was to kick in. No such order was issued before this newspaper's deadline.

U.S. District Judge Ronald Whyte of San Jose denied the plaintiffs a preliminary injunction Wednesday, finding their case isn't likely to succeed and the ban won't cause them irreparable harm. The right to possess such magazines "lies on the periphery of the Second Amendment," he wrote, and banning them is "substantially related to an important government interest."

"No court has yet entered a preliminary injunction against a law criminalizing the possession of magazines having a capacity to accept more than 10 rounds, nor has any court yet found that such a law infringes the Second Amendment," Whyte wrote.

Sunnyvale spokeswoman Jennifer Garnett said the ruling "is consistent with what a majority of our citizens clearly said they wanted when they passed the gun safety ordinance."

Chuck Michel, the NRA's West Coast counsel, said he's disappointed but not surprised, and "to protect the Second Amendment rights of Sunnyvale citizens, we will be seeking an emergency stay and expedited appellate review."

State law has banned the purchase of magazines holding more than 10 rounds since 2000; only those who owned them before then were allowed to register and keep them.

The NRA sued Dec. 16 to challenge the part of Measure C that requires owners of such magazines -- no matter when they were bought -- to remove them from the city, sell them outside California or to a licensed gun dealer, or give them up to police for destruction within 90 days. Measure C took effect Dec. 6, giving owners until March 6 to comply or become guilty of a misdemeanor.

Josh Richman covers politics. Contact him at 510-208-6428. Follow him at Twitter.com/josh_richman. Read the Political Blotter at IBAbuzz.com/politics.