The Virginia class of pre-dreadnought battleships were built for the United States Navy in the early 1900s. The class comprised five ships: Virginia, Nebraska, Georgia, New Jersey, and Rhode Island. The ships carried a mixed-caliber offensive battery of four 12-inch (305 mm) and eight 8-inch (203 mm) guns; these were mounted in an uncommon arrangement, with four of the 8-inch guns placed atop the 12-inch turrets. The arrangement proved to be a failure, as the 8-inch guns could not be fired independently of the 12-inch guns without interfering with them. Additionally, by the time the Virginias entered service, the first "all-big-gun" battleships—including the British HMS Dreadnought—were nearing completion, which would render mixed battery ships like the Virginia class obsolescent.
The Florida-class battleships of the United States Navy comprised two ships: Florida and Utah. Launched in 1910 and 1909 respectively and commissioned in 1911, they were slightly larger than the preceding Delaware class design but were otherwise very similar. This was the first US battleship class in which all ships received steam turbine engines. In the previous Delaware-class, North Dakota received steam turbine propulsion as an experiment while Delaware retained triple-expansion engines.
The Delaware-class battleships of the United States Navy were the second class of American dreadnoughts. With this class, the 16,000 long tons (16,257 t) limit imposed on capital ships by the United States Congress was waived, which allowed designers at the Navy's Bureau of Construction and Repair to correct what they considered flaws in the preceding South Carolina class and produce ships not only more powerful but also more effective and rounded overall. Launched in 1909, these ships became the first in US naval history to exceed 20,000 long tons (20,321 t).
The 14"/45 caliber gun,, whose variations were known initially as the Mark 1, 2, 3, and 5, and, when upgraded in the 1930s, were redesignated as the Mark 8, 9, 10, and 12. They were the first 14-inch (356 mm) guns to be employed with the United States Navy. The 14-inch/45 caliber guns were installed as the primary armament aboard all of the United States Navy's New York-class, Nevada-class, and Pennsylvania-class battleships. The gun also saw service in the British Royal Navy, where it was designated the BL 14 inch gun Mk II.
The 12″/45 caliber Mark 5 gun was an American naval gun that first entered service in 1906. Initially designed for use with the Connecticut-class of pre-dreadnought battleships, the Mark 5 continued in service aboard the first generation of American dreadnoughts.
The 16"/45 caliber Mark 6 gun is a naval gun designed in 1936 by the United States Navy for their Treaty battleships. It was first introduced in 1941 aboard their North Carolina-class battleships, replacing the originally intended 14"/50 caliber Mark B guns and was also used for the follow-up South Dakota class. These battleships carried nine guns in three three-gun turrets. The gun was an improvement to the 16"/45 caliber guns used aboard the Colorado class, and the predecessor to the 16"/50 caliber Mark 7 gun used aboard the Iowa class.
The 8"/35 caliber gun Mark 3 and Mark 4 were used for the main batteries of the United States Navy's first armored cruisers and the secondary batteries for their first battleships, the Indiana-class. The 8"/40 caliber gun Mark 5 initially armed the Pennsylvania-class armored cruisers.
The 10"/31 caliber gun Mark 1 Mod 1 and the 10"/35 caliber gun Mark 1 Mod 2 were both used for the primary batteries of the United States Navy's Amphitrite-class monitor Miantonomoh. The 10"/30 caliber gun Mark 2 was used as main armament on the remaining Amphitrite-class monitors, the monitor Monterey, and the armored cruiser Maine.
The 12"/35 caliber gun were used for the primary batteries of the United States Navy's "New Navy" monitors Puritan and Monterey and the battleships Texas and Iowa.
The 8"/45 caliber Mark 6 gun were used for the secondary batteries of the United States Navy's last pre-dreadnought battleships and refitted in older armored cruisers main batteries.
The 10"/40 caliber gun Mark 3 was used for the main batteries of the United States Navy's last generation of armored cruisers, the Tennessee-class. The Mark 3s were the last, and most powerful, 10-inch (254 mm) guns built for the US Navy.
The 7"/44 caliber gun Mark 1 and 7"/45 caliber gun Mark 2 were used for the secondary batteries of the United States Navy's last generation of pre-dreadnought battleships, the Connecticut-class and Mississippi-class. The 7-inch (178 mm) caliber was considered, at the time, to be the largest caliber weapon suitable as a rapid-fire secondary gun because its shells were the heaviest that one man could handle alone.
The 6"/40 caliber gun Mark 4 were used for the secondary batteries of the United States Navy's Indiana-class and Illinois-class battleships. They were also used as the main battery on the Cincinnati-class protected cruisers.
The 13"/35 caliber gun Mark 1 was used for the primary batteries on eight of the first nine battleships in the United States Navy, Indiana-class, Kearsarge-class and Illinois-class; USS Iowa (BB-4) used the 12-inch (305 mm)/35 caliber gun.
The 4"/40 caliber gun was used for the secondary batteries on the United States Navy's battleship Iowa, Columbia-class protected cruisers, and the armored cruiser New York, and was the primary batteries on the gunboats Nashville, Wilmington, and Helena.
The 5″/40 caliber gun were used in the secondary batteries of the United States Navy's early battleships, armored cruisers, protected cruisers, unprotected cruisers, and auxiliary cruisers.
The 5"/50 caliber gun was the first long barrel 5-inch (127 mm) gun of the United States Navy and was used in the secondary batteries of the early Delaware-class dreadnought battleships, various protected cruisers, and scout cruisers. They were also refitted in the secondary batteries of the armored cruiser New York and the New Orleans-class protected cruisers. They were later used on cargo ships, store ships and unclassified auxiliaries during World War II as well as in emergency coastal defense batteries.
The 12"/50 caliber Mark 7 gun was a United States Navy's naval gun that first entered service in 1912. Initially designed for use with the Wyoming-class of dreadnought battleships, the Mark 7 also armed the Argentine Navy's Rivadavia-class battleships.
The 6"/50 caliber gun Mark 6 and Mark 8 were used for the secondary batteries of the United States Navy's Maine-class and Virginia-class battleships, as well as the Pennsylvania-class and Tennessee-class armored cruisers. They were also used as the main battery on the St. Louis-class protected cruisers.
The 254 mm 45 caliber Pattern 1891 was a Russian naval gun developed in the years before the Russo-Japanese War that armed coastal defense ships and pre-dreadnought battleships during the Russo-Japanese War and World War I. Guns salvaged from scrapped ships found a second life as coastal artillery. It is believed none were in service during World War II.
