A dynamite gun is any of a class of artillery pieces distinguished by their specialized operating mechanism and purpose: they use compressed air to propel an explosive projectile. Dynamite guns were in use for a brief period from the 1880s to the beginning of the twentieth century. The guns fired a relatively lightweight shell; necessarily the guns had a low muzzle velocity, requiring a high angle of fire even at short ranges. This increased the flight time of the shell, and so resulted in a loss of accuracy. See External ballistics.