"OCT. 1, 2017 Fifty-eight people were killed and more than 500 were wounded when Stephen Paddock, from a perch high in a hotel, opened fire onto a crowd of concertgoers at an outdoor music festival in Las Vegas. Authorities recovered an arsenal of weapons — at least 23 from his hotel room — including AR-15-style rifles. SINCE 1982 Mr. Paddock started buying firearms in 1982, said Jill Snyder, a special agent in charge at the Bureau of Alcohol, Tobacco, Firearms and Explosives. WITHIN A YEAR OF THE SHOOTING Mr. Paddock legally purchased 33 firearms from Oct. 2016 to Sept. 2017, Ms. Snyder said. Most of those guns were rifles. Such purchases do not prompt reports to the bureau because there is no federal law requiring a seller to alert the bureau when a person buys multiple rifles. OCT. 1 Fifty-eight people were killed when Mr. Paddock fired onto the crowd of more than 22,000 from his hotel room at the Mandalay Bay Resort and Casino in Las Vegas. He used at least one semiautomatic rifle modified to fire like an automatic weapon by attaching a “bump stock,” not shown above. AFTER THE SHOOTING Authorities retrieved 47 guns from the hotel room and Mr. Paddock’s homes in Mesquite and Verdi, Nev. The bureau found Mr. Paddock purchased most of the guns in Nevada, Utah, California and Texas. Twelve of the rifles recovered from the hotel were each outfitted with a bump stock."