Autocannon

An autocannon or automatic cannon is a rapid-fire projectile weapon that fires armour piercing or explosive shells, as opposed to the bullet fired by a machine gun. Autocannons often have a larger calibre than a machine gun (e.g., 20 mm or greater). Usually, autocannons are smaller than a field gun or other artillery, and are mechanically loaded f...
Found on http://en.wikipedia.org/wiki/Autocannon

autocannon

French air defence weapon of World War I, consisting of a modified 75 mm field gun fitted to a special high-angle mounting and carried on a De Dion Bouton motor lorry. It became the standard...
Found on http://www.encyclo.co.uk/local/20688

Autocannon

The autocannon was a French air defence weapon of the Great War, consisting of a modified 75 mm field gun fitted to a special high-angle mounting and carried on a De Dion Bouton motor lorry. It became the standard anti-aircraft gun in France, used for the defence of forward as well as rear areas and cities, although its use declined as motorised gu...
Found on http://www.probertencyclopaedia.com/browse/FYA.HTM
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