Im trying to find a movie it was about a guy that would throw these circular creatures at people and they would stick to them and kill them and they would clamp into peoples skin and kill them. The creatures were round and a little bit bigger than a dvd with either teeth or claws around the edges that would clamp into people when thrown and kill them after being threw by this guy. It came out between 78-83. They were round and had teeth or either claws around the edges but he threw them as a weapon.

Sounds like 1980's Without Warning (http://www.imdb.com/title/tt0081764/).

The movie is called critters it came out in 1986.