SACRAMENTO (AP) — BB guns and pellet guns would have to look clearly different from those that fire bullets to be sold in California under a bill approved Tuesday by the state Senate in response to several recent shooting tragedies involving children.Senators approved the Imitation Firearm Safety Act on a party-line 22-8 vote, although several senators from each party did not vote. It now goes to the Assembly.SB199 advanced in the wake of the October fatal shooting of 13-year-old Andy Lopez in Santa Rosa, when a sheriff’s deputy mistook the boy’s “airsoft” rifle for a real AK-47. Airsoft guns are replica firearms that fire plastic pellets, paper balls or eraser chunks.“The tragedy has rocked Santa Rosa and Sonoma County to its very core,” said Sen. Noreen Evans, D-Santa Rosa, a co-author of the bill.