gun law, not a loophole. that may make no sense to you. this will make even more sense. kits you can buy orchl to turn a semi-automatic rival into a fully automatic weapon. legal to buy yet illegal to actually use. >> anybody with a basic machining skillset could go ahead and convert a semi-automatic rival to a fully automatic rifle. the conversion kit is legal but when you use it to convert to it fully automatic it is an illegal firemen. >> reporter: the shooter may have used both firing into a second story into a huge crowd needed little training, if any, to kill so many. any attempt with guns is likely to go nowhere with a republican congress. even after the sandy hook