12.7×55mm STs-130

12.7×55mm
Type	Rifle
Place of origin	Soviet Union Russia
Specifications
Parent case	.338 Lapua Magnum
Bullet diameter	12.7 mm (0.50 in)
Case length	54 mm (2.1 in)
Overall length	94 mm (3.7 in)

The 12.7×55mm Subsonic cartridge is used in the VKS bullpup sniper rifle. The cartridge can carry a projectile weighing between from 59 grams (911 grains) and 76 g (1173 gr), yielding massive amounts of kinetic energy. The round can penetrate up to 16 mm (0.63 in) of steel at 200 meters or heavy body armor at 100 meters. The accuracy of this cartridge is claimed as to be 1 MOA at 100 meters range.

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Wikipedia