A federal judge on Thursday blocked a California law requiring background checks for people buying ammunition, issuing a sharply worded rebuke of “onerous and convoluted” regulations that violate the constitutional right to bear arms.

U.S. District Judge Roger Benitez in San Diego ruled in favor of the California Rifle & Pistol Association, which asked him to stop the checks and related restrictions on ammo sales.

“The experiment has been tried. The casualties have been counted. California’s new ammunition background check law misfires and the Second Amendment rights of California citizens have been gravely injured,” Benitez wrote in a 120-page opinion granting the group’s motion for a preliminary injunction.