page_title: USS Iowa (BB-4)
section_title: Armament
hierarchical_section_title: USS Iowa (BB-4) / Design / Armament
caption_attribution_description: English: (Battleship # 4) Sailors and Marines of the ship's crew posed in front of her forward 12/35 gun turret, circa August 1898. Photographed by William H. Rau. Note that Iowa has been partially repainted from wartime grey. Also note the ship's bell below the pilothouse. USS Brooklyn (Armored Cruiser # 3) is in the right distance.
context_page_description: USS Iowa (BB-4) was a pre-dreadnought battleship built for the United States Navy in the mid-1890s. The ship was a marked improvement over the previous Indiana-class battleships, correcting many of the defects in the design of those vessels. Among the most important improvements were significantly better seaworthiness owing to her greater freeboard and a more efficient arrangement of the armament. Iowa was designed to operate on the high seas, which had been the impetus to increase the freeboard. She was armed with a battery of four 12-inch guns in two twin-gun turrets, supported by a secondary battery of eight 8-inch guns.
  Upon entering service in June 1897, Iowa conducted training operations in the Atlantic Ocean before moving to the Caribbean in early 1898 as tensions between the United States and Spain over Cuba grew, leading to the Spanish–American War. The ship took part in the bombardment of San Juan, Puerto Rico, and then participated in the blockade of Cuba during the war, and after the Spanish cruiser squadron was found in Santiago de Cuba, she patrolled off the harbor to block their escape.
context_section_description: Iowa was armed with a main battery of four 12 in (305 mm)/35 caliber guns mounted in two twin-gun turrets that were mounted on the centerline, one forward and the other aft of the superstructure. The built-up guns were the Mark II type, which were placed in elliptical Mark III turrets. The training gear was hydraulically operated, but elevation was hand-operated only. The gun mounts allowed elevation to 14 degrees and depression to −5 degrees; to reload the guns, they had to be returned to 3 degrees elevation. The ammunition hoists that retrieved shells and propellant charges from the magazines were also hydraulically operated. The guns fired an 850 lb (390 kg) shell with a 425 lb (193 kg) charge of brown powder. Muzzle velocity was 2,100 ft/s (640 m/s), and at the muzzle, the shells could penetrate up to 24 in (610 mm) of mild steel; at a range of 2,500 yd (2,300 m), their penetration capability fell to 19 in (483 mm). The average rate of fire was one shot every five minutes, though fresh, well-trained crews could achieve rates as fast as one shot every three minutes.
  The primary armament was supported by a secondary battery of eight 8 in (203 mm)/35 cal guns that were carried in four twin-gun wing turrets. Two were placed on either side of the ship, abreast of the funnels. Since the 12-inch guns had a long reloading time, the 8-inch guns were incorporated to increase the number of weapons that could defeat light armor. The 8-inch guns were the Mark IV version, which had a rate of fire of one shot per minute. They had a muzzle velocity of 2,080 ft/s (630 m/s), firing 250 lb (110 kg) armor-piercing shells. They were initially supplied with brown powder charges, but after the advent of smokeless powder, new, smokeless charges were adopted that increased the rate of fire by twenty seconds. Mounted in Mark VIII turrets with a range of elevation from −7 to 13 degrees, reloading was fixed at 0 degrees. 
  Six 4 in (100 mm)/40 cal quick-firing guns rounded out the secondary battery; these were intended to use their high rate of fire, coupled with high-explosive shells to damage unarmored parts of enemy warships. Four of these were placed in individual casemates in the forecastle deck, two in sponsons in the bow and the other two located amidships. The remaining two guns were in open shielded mounts on the aft superstructure, superfiring over the rear main battery turret. They fired a 33 lb (15 kg) high-explosive shell at a muzzle velocity of 2,000 ft/s (610 m/s). For defense against torpedo boats, the ship carried a battery of twenty 57 mm (2.2 in) 6-pounder Hotchkiss guns and four 37 mm (1.5 in) 1-pounder guns These guns were dispersed around the ship in a variety of individual mounts, including in the fighting top of the military mast, the superstructure, and in sponsons in the hull. She also carried four M1895 Colt–Browning machine guns chambered in 6mm Lee Navy.
  As was standard practice for capital ships of the era, Iowa carried four above-water, 14-inch (356 mm) torpedo tubes in her hull, two on each broadside. These launched the Howell torpedo, which had a range of 400 yards (370 m) and traveled at a speed of 25 knots (46 km/h; 29 mph). They carried a 400 lb (180 kg) warhead.
caption: Iowa's forward main battery turret; one of her secondary turrets is visible at right
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