Look here --- It should give you a little background ..
http://www.msgunowners.com/gun-laws-f9/50cal-used-to-shoot-a-melon-off-a-man-s-head-reckless-endangerment-t10203.htm
http://www.msgunowners.com/general-firearms-discussion-f16/which-one-of-you-have-the-50-t10294.htm
http://www.msgunowners.com/general-firearms-discussion-f16/anyone-know-these-guys-t10231.htm