37×3003

37x3003 refers to a specific type of projectile, commonly a rifle cartridge. The designation indicates the bore diameter and the length of the cartridge case. The "37" denotes a nominal bore diameter of 37 millimeters, which is approximately 1.457 inches. The "3003" signifies the length of the cartridge case, which is 30.03 millimeters or approximately 1.182 inches. This particular cartridge was developed and used primarily in the early 20th century.

The 37x3003 cartridge was often associated with anti-tank rifles and other specialized infantry support weapons. Its design aimed to provide a balance of projectile weight, velocity, and penetration capabilities for its intended role. Weapons chambered for this ammunition were typically bolt-action or semi-automatic rifles. The relatively small caliber, despite the "37" designation, means it's not a modern autocannon round but rather a rifle-caliber projectile.

While not as widely known or produced as some other historical cartridges, the 37x3003 played a role in the evolution of anti-materiel and anti-personnel rifle development. Its historical significance lies in its contribution to early attempts at giving infantry the ability to engage armored targets at range. Ammunition for this caliber is now considered obsolete and is primarily of interest to firearms collectors and historical researchers.