Medium Caliber Weapons

Traditionally, "medium caliber" refers to weapons systems larger in caliber than .50 caliber machine guns and usually includes cannons in the 20mm through 60mm caliber range. Projectiles in this caliber range are large enough to have an explosive charge included as part of their lethal mechanism. Most cannons of this size are automatic and are capable of firing bursts of ammunition.

Medium caliber automatic cannon systems were widely used in World War II as armaments for fighter aircraft and as air defense weapons for both ground and shipboard use. This proliferation of medium caliber automatic cannons continued during the Korean and Vietnam Wars. In the Vietnam conflict, the automatic cannon was married to the helicopter creating a new weapons system, the Attack Helicopter. In similar fashion, the 1970s saw the emergence of the Infantry Fighting Vehicle, an armored vehicle capable of providing protected transport of troops as well as providing suppressive and defensive fire with automatic cannons and other weapons. Picatinny played an integral role in the development and integration of automatic cannons and cannon ammunition for Attack Helicopters and Infantry Fighting Vehicles.