The USS Arizona was the biggest ship at the time. She had 14 inch 45 caliber cannons that could shoot almost a mile away and hit enemy ship . Those were its main cannons that it used for defense. Its secondary cannons were 5 inches 51 caliber cannons. Those were the smaller round that they used for speed firing. Some of its anti-aircraft guns are 5 inches 25 caliber machine guns. The secondary type of anti-aircraft gun they used on that ship was the 50 caliber machine gun.