An ammunition dealer who has acknowledged selling hundreds of rounds of tracer bullets to a gunman responsible for killing 58 people in Las Vegas was charged on Friday with conspiracy to make and sell armor-piercing ammunition without a license.Douglas Haig, 55, of the Phoenix suburb of Mesa, Arizona, became the first person arrested and charged in connection with the Oct. 1 massacre, which ended when the perpetrator, Stephen Paddock, killed himself.But Haig told a news conference at the office of his attorney on Friday that none of the surplus military ammunition he sold Paddock in September was ever fired during the killing spree, which ranks as the deadliest mass shooting in modern US history. Nearly 500 people were injured.