sentences:  They were used extensively during the English Civil Wars in the 1640s and 1650s, especially in Scotland.Cannon in the early 17th century were of a plethora of calibers.In order to simplify logistics Gustavus Adolphus reduced the number of calibers to guns firing 24-, 12- and 6-pound cannonballs (roughly 10, 5 & 2.5 kg) .