It is common misconception that the length of the Vickers ammunition belt is the origin of the saying ‘give them the whole nine yards’. This is not the case and the Vickers belt was only 6 2/3 yards (6.1 metres or 20 feet).
The origins of the phrase are much older and it may later be applied, as a generic saying, to machine guns and particularly more likely for aircraft machine guns that carried 400 rounds rather than the 250 rounds for ground guns.
