U-T SACRAMENTO BUREAU OVERVIEW Background: In 2007, the Legislature passed a bill that requires new models of semiautomatic handguns to leave an identifying code on shell casings. The law is scheduled to take effect Jan. 1. What's changing: Unresolved legal issues and concerns about the technology have raised questions about whether the law will go into effect as planned. The future: Efforts by other states and the federal government to adopt similar rules may lag if implementation of the California law becomes problematic. SACRAMENTO – Two years after California passed a novel law requiring the next generation of semiautomatic handguns...