520 mm artillery
= 520 mm artillery
{wiki=Category:520_mm_artillery}
The term "520 mm artillery" typically refers to large-caliber artillery pieces that have a bore diameter of 520 millimeters. This caliber is notably larger than standard artillery used in most conventional military applications. An example of a 520 mm artillery piece is the Soviet "K欲" (also known as "Katushka" or "K-3," which is a railway gun).