These rifles are semi-automatic....meaning you pull the trigger, a shot fires and another round is chambered...ready to fire.  You must then pull the trigger again to fire the second, third...............maybe up to 30th or so round, depending on the capacity of the magazine.  These guns are designed to mimick Assault Rifles, which are fully automatic (single shot, bursts, or shoot the full magazine) and,  with that feature, are illegal to sell in the US, other than to exempted buyers.  I'm not a gun guy, but I'd bet some of these "legal" rifles are exactly like the fully automatic, except for that feature..and with a few parts could easily be modified to fully automatic....gun guys..is this correct?  Still, they are perfectly legal under current law.  High capacity magazines.....not OK for hunting...to my knowledge all states limit hunting magazines to five rounds.....three shotgun shells for migratory waterfowl.  Need?  that one is an endless debate.....  Gary Crum