From the 18th century British Navy. They began refitting their cannons aboard battleships to penetrate newer ironclad ships. To do this, the cannons used considerably more powder, and were much heavier, but on many of the ships, the support structures were not reinforced to accommodate the extra stress. As a result, many of these cannons became dislodged by the kickback and would often fly off the deck or roll around loose, causing damage and injury.
Loose CannonSomeone who is unpredictable can be referred to as a wild card. Also, the term loose cannon is occasionally used, though that usually carries a meaning of being quick to anger as well.
The cast of Loose Cannon - 2007 includes: Matthew Bone Mason Reynolds
Loose Cannon, a character in the DC Comics universe, was created by Denny O'Neil and Dick Giordano in 1991. The character first appeared in "Action Comics" #665.
Wiseguy - 1987 The Loose Cannon - 1.3 was released on: USA: 1 October 1987
A "loose cannon" is someone who gets upset or angry easily, and who acts without thinking. So in a crowd of people the loose cannon would be the one who gets upset and starts something--maybe just yelling, or maybe violence.
A loose canon is someone who is unpredictable and possibly dangerous.
Wiseguy - 1987 The Loose Cannon 1-3 was released on: USA: 1 October 1987
Katts and Dog - 1988 Loose Cannon 4-17 is rated/received certificates of: Canada:PG USA:PG
Today springs are used to check recoil, but in the days of HMS Victory the cannon were on wheeled carriages, with ropes to stop them from recoiling too far when fired. Also, the ship pitched when sailing, especially in the rough seas, and the term "loose cannon" originally referred to a ship's cannon loosed from its rope and rolling dangerously on the deck.
Intestinology, if I can derive a term for it
Europe
"Ninety-Three" - A formidable character, Marquis de Lantenac, who is leading a monarchist insurrection is smuggled on a boat from England. He saves the life of a seaman who stops a loose cannon from destroying the ship, and then executes him for letting the cannon go loose in the first place.