Helge Palmcrantz invented the machine gun around 1914. They could fire 400-600 small-calibre rounds per minute, but there was a problem, the early machine guns would rapidly overheat and become inoperative without the aid of cooling mechanisms; they were consequently fired in short rather than sustained bursts. The first machine gun was made by Hiram Maxim, he used a simple concept.

via Tumblr http://ift.tt/1N5Tr71