The National Shooting Sports Foundation is calling on the federal Bureau of Alcohol, Tobacco, Firearms and Explosives to review and evaluate aftermarket trigger activation devices such as bump stocks.  The Newtown-based gun industry trade association says it should be determined whether regulations are needed after the device was used by the  Las Vegas gunman to kill 58 and injured more than 500.  NSSF says if bump stocks have no other purpose than to convert a conventional firearm into an automatic firearm, they could be regulated.  The group stopped short of calling for a ban.