A New Mexico jury found "Rust" armourer Hannah Gutierrez guilty of involuntary manslaughter, ending a trial over Hollywood's first on-set fatal shooting in nearly 30 years. Ten days of testimony had focused on whether the relatively inexperienced armourer endangered fellow crew and cast members in her handling and supervision of firearms on the low-budget production set in New Mexico. Judge Mary Marlowe Sommer ordered that Gutierrez be taken into custody immediately. She faces up to 18 months in state prison. As deputies led her from the courtroom, Gutierrez told her distraught mother, "I'll be okay." Jurors, who reached their decision…