The term "350 mm artillery" typically refers to large-caliber artillery pieces designed to fire projectiles with a diameter of 350 millimeters (mm). Such artillery systems can include howitzers, mortars, or coastal defense guns. These types of artillery are typically used for heavy bombardment in military operations and can cause significant destruction due to the large size of the shells they fire.

340 mm artillery typically refers to large-caliber artillery pieces that have a bore diameter of 340 millimeters (approximately 13.4 inches). These types of artillery are most often associated with heavy howitzers or coastal defense guns and are used for long-range bombardment, siege warfare, or fortification support. One notable example of 340 mm artillery is the **"340 mm howitzer Model 1939,"** which was used by the Soviet Union during World War II.

The term "330 mm artillery" typically refers to large-caliber artillery pieces that fire projectiles with a 330 mm diameter. Such large-caliber artillery systems can be used in various military applications, including siege warfare, long-range bombardment, and indirect fire support. One notable example of 330 mm artillery is the **BM-30 Smerch**, a multiple rocket launcher system developed in the Soviet Union.

The term "320 mm artillery" typically refers to heavy artillery pieces that have a caliber of 320 millimeters. This caliber is relatively uncommon and is not typically found in standard field artillery. One of the most notable pieces of artillery that fits this classification is the **320 mm gun** developed for specific military purposes.

305 mm artillery typically refers to artillery pieces that have a bore diameter of 305 millimeters (approximately 12 inches). This caliber has been used in various types of artillery systems, including howitzers, cannons, and coastal defense guns, throughout military history. The 305 mm caliber was notably employed during the early to mid-20th century, particularly in World War I and World War II.

300 mm artillery typically refers to large-caliber artillery pieces that fire projectiles with a diameter of 300 millimeters (30 cm). This size of artillery is often associated with heavy howitzers or siege guns, which are designed for long-range bombardment and can deliver powerful explosive shells over significant distances. Historically, 300 mm artillery has been used in many military conflicts and can be mounted on both towed and self-propelled platforms.

The term "280 mm artillery" generally refers to a type of large-caliber artillery piece that fires 280 mm (approximately 11 inches) projectiles. One of the most notable examples of 280 mm artillery is the **M65 atomic cannon**, which was developed by the United States in the early Cold War period. The M65 was designed to be capable of firing nuclear projectiles, making it a significant part of the U.S.

The term "274 mm artillery" typically refers to a type of large-caliber artillery piece with a bore diameter of 274 millimeters (approximately 10.8 inches). One of the most notable examples of this caliber is the **274 mm gun** developed during World War II by several countries, including the Soviet Union and Germany.

The term "260 mm artillery" typically refers to artillery pieces that have a caliber of 260 millimeters. One of the most notable examples of 260 mm artillery is the Soviet M-260, a heavy mortars system developed in the mid-20th century. It was a part of a category of large-caliber artillery designed for long-range bombardment and support of ground forces.

The term "254 mm artillery" typically refers to large-caliber artillery systems that use 254 mm shells. While 254 mm isn't a standard caliber in modern artillery, this dimension can be associated with specific historical artillery pieces. One notable example is the **254 mm howitzer**, which was used by some military forces during the 20th century.

250 mm artillery typically refers to a type of heavy artillery piece that fires projectiles with a diameter of 250 millimeters (approximately 9.8 inches). This size falls into the category of large caliber artillery systems, which were primarily used during wars to deliver significant firepower over long distances.

240 mm artillery refers to a type of large-caliber artillery piece that fires projectiles with a diameter of 240 millimeters (or about 9.45 inches). This caliber of artillery is typically used for heavy bombardment and is capable of delivering significant explosive power over long distances.

The term "234 mm artillery" typically refers to artillery pieces or ammunition with a caliber of 234 millimeters. This specific caliber is not among the most commonly used in modern artillery systems, as most artillery pieces are typically measured in more standard calibers such as 105 mm, 155 mm, or 203 mm. However, artillery of this caliber could be related to specific historical weapons or specialized systems used in particular military forces.

230 mm artillery typically refers to a type of large-caliber artillery piece that fires projectiles with a diameter of 230 millimeters. This caliber is not among the most common artillery sizes, which often range from 105 mm to 155 mm for field artillery. However, 230 mm guns can be found in the form of howitzers, mortars, or self-propelled artillery systems.

225 mm artillery typically refers to a type of large caliber artillery piece that fires 225 mm (approximately 8.9 inches) diameter shells. This caliber of artillery is generally used for heavy bombardment and can deliver high-explosive, fragmentation, or specialized munitions over considerable distances.

The term "220 mm artillery" refers to a type of large-caliber artillery projectile with a diameter of 220 millimeters. This caliber is notably used in various artillery systems designed to provide heavy fire support, typically in military operations. Various countries have developed 220 mm artillery systems, with one of the most well-known being the Soviet/Russian 220 mm self-propelled multiple rocket launchers and artillery pieces.

The term "210 mm artillery" typically refers to a class of artillery pieces that have a caliber (the diameter of the gun barrel) of 210 millimeters. This size of artillery is often used for heavy bombardment and is capable of firing large, high-explosive shells over significant distances. The most notable example of 210 mm artillery is the Soviet 2S7 Pion, a self-propelled gun that was designed to provide fire support and destroy hardened targets.

203 mm artillery typically refers to howitzers that fire shells with a diameter of 203 millimeters (8 inches). This caliber of artillery is known for its significant firepower and is used for long-range bombardment, support for ground troops, and to destroy fortified positions. Historically, 203 mm artillery has been utilized by various countries, particularly during the 20th century.

The term "194 mm artillery" typically refers to a type of artillery piece that fires shells with a diameter of 194 millimeters. This caliber falls between the more common 105 mm, 155 mm, and larger artillery systems. The specific design and characteristics of a 194 mm artillery piece can vary significantly depending on its intended use and the era in which it was produced.

190 mm artillery refers to a category of heavy artillery piece that has a bore diameter of 190 millimeters (approximately 7.48 inches). This caliber was used primarily during the 20th century and includes various types of guns, howitzers, and other artillery systems designed for long-range bombardment and fire support roles on the battlefield.