12.7×55mm STs-130

The 12.7×55mm STs-130 is a cartridge used in Russian firearms such as the VKS bullpup sniper rifle, the ShAK-12 bullpup battle rifle, and the RSh-12 revolver. It can carry a projectile weighing between 108 and 1173 grains and is predominantly used to fire heavy subsonic loads; the high-penetration VKS round can penetrate up to 16 millimeters of steel at 200 meters or body armor up to GOST 5A or NIJ III at 100 meters. Despite being chambered in the same cartridge, the ShAK-12 and RSh-12 cannot feed or chamber rounds designed for the VKS because of differences in bullet length, and require their own shorter loads. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/