Most stories I've read was about the US experience with then. Always wondered if it was better in the original chambering. Guess it was, though not great at any rate.
http://nationalinterest.org/blog/the-buzz/the-shocking-story-the-worst-machine-gun-ever-made-25459
http://nationalinterest.org/blog/the-buzz/the-shocking-story-the-worst-machine-gun-ever-made-25459