All these folks worried about a single shot plastic gun, hasn’t anyone heard of a zip gun, which all you need is a small tube to fit the bullet, a rubber band and a nail? Not to mention how many hours, maybe days it could take to print one of these out on a simple 3D printer.
http://www.cnn.com/2013/05/07/opinion/ferguson-printable-gun/index.html?iid=article_sidebar