The 3-inch anti-aircraft gun M3 was an anti-aircraft gun which served throughout the 1930s and possibly into early World War II. Developed from the earlier 3-inch M1917 and 3-inch M1918 guns, it was in the process of being replaced by the time of the US entry into World War II, but was subsequently adapted into an anti-tank gun role, both free-standing and in a self-propelled tank destroyer.

The 3-inch gun M1903 and its predecessors the M1898 and M1902 were rapid fire breech-loading artillery guns with a 360-degree traverse. In some references they are called "15-pounders" due to their projectile weight. They were originally emplaced from 1899 to 1917 and served until shortly after World War II. These 3-inch guns were placed to provide fire to protect underwater mines and nets against minesweepers, and also to protect against motor torpedo boats. In some documentation they are called "mine defense guns". The 3-inch guns were mounted on pedestal mounts that bolted into a concrete emplacement that provided cover and safety for the gun's crew.

The 4.5 inch gun M1 was a field gun developed in the United States in the beginning of World War II. It shared the same carriage with the 155mm Howitzer M1 and fired the same ammunition as the British BL 4.5 inch Medium Field Gun. Beginning in 1944, the weapon was used by the U.S. Army as corps-level artillery; with the end of hostilities, it was declared obsolete.

The 6-inch gun M1897 (152 mm) and its variants the M1900, M1903, M1905, M1908, and M1 were coastal artillery pieces installed to defend major American seaports between 1897 and 1945. For most of their history they were operated by the United States Army Coast Artillery Corps. They were installed on disappearing carriages or pedestal mountings, and during World War II many were remounted on shielded barbette carriages. Most of the weapons not in the Philippines were scrapped within a few years after World War II.

The 8-inch gun M1 was a 203 mm towed heavy gun developed in the United States. At 32,584 m (35,635 yd), it had the longest range of any US Army field artillery weapon in World War II. It was also used in small numbers by the British Army.

The 8-inch gun M1888 (203 mm) was a U.S. Army Coast Artillery Corps gun, initially deployed 1898–1908 in about 75 fixed emplacements, usually on a disappearing carriage. During World War I, 37 or 47 of these weapons were removed from fixed emplacements or from storage to create a railway gun version, the 8-inch Gun M1888MIA1 Barbette carriage M1918 on railway car M1918MI, converted from the fixed coast defense mountings and used during World War I and World War II.

The 8-inch Navy gun Mk.VI M3A2 on railway mount M1A1 was a World War II improved replacement for the World War I-era 8-inch M1888 gun and was used by the US Army's Coast Artillery Corps in US harbor defenses. The guns were also mounted in fixed emplacements on the barbette carriage M1A1. These guns were US Navy surplus 8"/45 caliber guns from battleships scrapped under the 1922 Washington Naval Treaty. Mark VI was the Navy designation. The Army designation for this gun was "8-inch Navy gun Mk.VI M3A2".

The 10-inch Gun M1895 (254 mm) and its variants the M1888 and M1900 were large coastal artillery pieces installed to defend major American seaports between 1895 and 1945. For most of their history they were operated by the United States Army Coast Artillery Corps. Most were installed on disappearing carriages, with early installations on barbette mountings. All of the weapons not in the Philippines were scrapped during World War II. Two of the surviving weapons were relocated from the Philippines to Fort Casey in Washington state in the 1960s.

The 12-inch coast defense mortar was a weapon of 12-inch (305 mm) caliber emplaced during the 1890s and early 20th century to defend US harbors from seaborne attack. In 1886, when the Endicott Board set forth its initial plan for upgrading the coast defenses of the United States, it relied primarily on mortars, not guns, to defend American harbors. Over the years, provision was made for fortifications that would mount some 476 of these weapons, although not all of these tubes were installed. Ninety-one of these weapons were remounted as railway artillery in 1918-1919, but this was too late to see action in World War I. The railway mortars were only deployed in small quantities, and none overseas. The fixed mortars in the Philippines saw action in the Japanese invasion in World War II. All of the fixed mortars in the United States were scrapped by 1944, as new weapons replaced them, and the railway mortars were scrapped after the war. Today, the only remaining mortars of this type in the 50 states are four at Battery Laidley, part of Fort Desoto near St. Petersburg, Florida, but the remains of coast defense mortar emplacements can be seen at many former Coast Artillery forts across the United States and its former territories. Additional 12-inch mortars and other large-caliber weapons remain in the Philippines.

The 12-inch coastal defense gun M1895 (305 mm) and its variants the M1888 and M1900 were large coastal artillery pieces installed to defend major American seaports between 1895 and 1945. For most of their history they were operated by the United States Army Coast Artillery Corps. Most were installed on disappearing carriages, with early installations on low-angle barbette mountings. From 1919, 19 long-range two-gun batteries were built using the M1895 on an M1917 long-range barbette carriage. Almost all of the weapons not in the Philippines were scrapped during and after World War II.

The 14-inch Gun M1907 (356 mm) and its variants the M1907MI, M1909, and M1910 were large coastal artillery pieces installed to defend major American seaports between 1895 and 1945. They were operated by the United States Army Coast Artillery Corps. Most were installed on single gun disappearing carriages; the only installation with four guns in twin turrets was built at the unique Fort Drum in Manila Bay, Philippines. All of the weapons not in the Philippines were scrapped during World War II.

The 14-inch M1920 railway gun was the last model railway gun to be deployed by the United States Army. It was an upgrade of the US Navy 14"/50 caliber railway gun. Only four were deployed; two in the Harbor Defenses of Los Angeles and two in the Panama Canal Zone, where they could be shifted between the harbor defenses of Cristobal (Atlantic) or Balboa (Pacific).

The 16-inch coastal defense gun M1895 was a large artillery piece installed to defend major American seaports. Only one was built and it was installed in Fort Grant on the Pacific side of the Panama Canal Zone. It was operated by the United States Army Coast Artillery Corps.

The 16-inch howitzer M1920 (406 mm) was a coastal artillery piece installed to defend major American seaports between 1922 and 1947. They were operated by the United States Army Coast Artillery Corps. They were installed on high-angle barbette mountings to allow plunging fire. Only four of these weapons were deployed, all at Fort Story, Virginia. All were scrapped within a few years after World War II.

The 75 mm Field Gun M1897 on M2 Carriage was a field gun and anti-tank gun which was used by the US Army during the interwar period and World War II.

The 75 mm gun was the standard American gun mounted to a mobile platform during World War II. They were primarily mounted on tanks, but were also mounted on the B-25 Mitchell medium bomber aircraft. There were five variants used during the war: M2, M3, M4, M5, and M6.

The 76 mm gun M1 was an American World War II–era tank gun developed by the U.S Ordnance Department in 1942 to supplement the 75 mm gun on the basic Medium tank M4. It was also used to arm the M18 Hellcat tank destroyer.

105mm gun T8 was an anti-tank gun developed in the United States in mid-1940s. This gun's design was influenced by German 88 mm Pak 43/41 anti-tank guns captured by the U.S. Army in France. The development started in October 1944; the gun reached trials in February 1946. Soon afterwards the project was cancelled.

The 155 mm gun M1 was a 155 millimeter caliber field gun developed and used by the United States military. Nicknamed "Long Tom", it was produced in M1 and M2 variants, later known as the M59. Developed to replace the Canon de 155mm GPF, the gun was deployed as a heavy field weapon during World War II and the Korean War, and also classed as secondary armament for seacoast defense. The gun could fire a 100 lb (45 kg) shell to a maximum range of 14 mi (23 km), with an estimated accuracy life of 1,500 rounds.

The 240 mm howitzer M1, popularly nicknamed the "Black Dragon", was a towed howitzer used by the United States Army. The 240 mm M1 was designed to replace the World War I era 240 mm howitzer M1918, which was based on a 1911 French design and was outdated by World War II.

The Canon de 155 Grande Puissance Filloux (GPF) mle.1917 was a WWI-era French-designed 155 mm gun used by the French Army and the United States Army during the first half of the 20th century in towed and self-propelled mountings.

The U.S. Army Coast Artillery Corps (CAC) was an administrative corps responsible for coastal, harbor, and anti-aircraft defense of the United States and its possessions between 1901 and 1950. The CAC also operated heavy and railway artillery during World War I.

A disappearing gun, a gun mounted on a disappearing carriage, is an obsolete type of artillery which enabled a gun to hide from direct fire and observation. The overwhelming majority of carriage designs enabled the gun to rotate backwards and down behind a parapet, or into a pit protected by a wall after it was fired; a small number were simply barbette mounts on a retractable platform. Either way, retraction lowered the gun from view and direct fire by the enemy while it was being reloaded. It also made reloading easier, since it lowered the breech to a level just above the loading platform, and shells could be rolled right up to the open breech for loading and ramming. Other benefits over non-disappearing types were a higher rate of repetitive fire and less fatigue for the gun crew.

The M2 4.2-inch mortar was a U.S. rifled 4.2-inch (107 mm) mortar used during the Second World War and the Korean War. It entered service in 1943. It was nicknamed the "Goon Gun" or the "Four-Deuce". In 1951 it began to be phased out in favor of the M30 mortar of the same caliber.

The 105 mm Howitzer M3 was a U.S. light howitzer designed for use by airborne troops. The gun utilized the barrel of the 105 mm Howitzer M2, shortened and fitted to a slightly modified split trail carriage of the 75 mm pack howitzer.

The 105 mm M101A1 howitzer is an artillery piece developed and used by the United States. It was the standard U.S. light field howitzer in World War II and saw action in both the European and Pacific theaters. Entering production in 1941, it quickly gained a reputation for accuracy and a powerful punch. The M101A1 fires 105 mm high explosive (HE) semi-fixed ammunition and has a range of 12,330 yards (11,270 m), making it suitable for supporting infantry.

The M114 155 mm howitzer is a towed howitzer developed and used by the United States Army. It was first produced in 1942 as a medium artillery piece under the designation of 155 mm Howitzer M1. It saw service with the US Army during World War II, the Korean War, and the Vietnam War, before being replaced by the M198 howitzer.

The M115 203 mm howitzer, also known as the M115 8 inch howitzer, and originally 8 inch Howitzer M1 was a towed howitzer developed and used by the United States Army.

The 75mm Pack Howitzer M1 was an artillery piece used by the United States. It was designed in the 1920s to meet a need for a howitzer that could be moved across difficult terrain. The gun and carriage were designed so that it could be broken down into several pieces to be carried by pack animals. The gun saw combat in World War II with the United States Army, with the United States Marine Corps, and was also supplied to foreign forces.

The Rocket Launcher T34 (Calliope) was a tank-mounted multiple rocket launcher used by the United States Army during World War II. The launcher was placed atop the M4 Sherman, with its prominent vertical side frames anchored to the turret's sides, and fired a barrage of 4.5 in (114 mm) M8 rockets from 60 launch tubes. It was developed in 1943; small numbers were produced and were used by various US armor units in 1944–45. It adopts its name from the musical instrument "Calliope", also known as the steam organ, which had similar parallel or clustered pipes.

The Rocket Launcher T40/M17 (Whizbang) was a tank-mounted multiple rocket launcher used by the United States Army during World War II. The launcher was placed atop the Medium Tank M4, and fired a barrage of 7.2 in (180 mm) T37 HE or T21 Chemical rockets from 20 launch tubes. It was developed and used in the late stages of World War II; it saw limited combat in 1944–45. An experimental short variant of the T40 was also developed.
