In this July 20, 2012, file photo, a row of different AR-15 style rifles are displayed for sale at the Firing-Line indoor range and gun shop in Aurora, Colo.
In this July 20, 2012, file photo, a row of different AR-15 style rifles are displayed for sale at the Firing-Line indoor range and gun shop in Aurora, Colo. Alex Brandon AP FILE
In this July 20, 2012, file photo, a row of different AR-15 style rifles are displayed for sale at the Firing-Line indoor range and gun shop in Aurora, Colo. Alex Brandon AP FILE