12.7×55mm STs-130

• Name — 12.7×55mm • Origin — Russian Federation • Type — Rifle • Design Date — 2002 • Is Si Specs — yes • Parent —.338 Lapua Magnum • Bullet — 13.01 mm • Shoulder — 13.76 • Base — 14.86 • Case Length — 54.91 mm • Length — STs-130 - 97.3 mm PS-12 - 73 mm • Is Si Ballistics — yes • Bwunit — gram • Bw1 — 59 • Btype1 — STs130PT • Vel1 — 295 • En1 — 2567 • Bw2 — 48.2 • Btype2 — STs130PT2 • Vel2 — 295 • En2 — 2097 • Bw3 — 76 • Btype3 — STs130VPS • Vel3 — 295 • En3 — 3307 • Bw4 — 33 • Btype4 — PS-12 • Vel4 — 300 • En4 — 1485 • Bw5 — 17.94 • Btype5 — PS-12B • Vel5 — 300 • En5 — 807.3 The 12.7×55mm cartridge is used in some Russian firearms such as the VKS bullpup sniper rifle, the ShAK-12 bullpup battle rifle and the RSh-12 revolver. The cartridge can carry a projectile weighing between 108 grains and 1173 grains and is predominantly used to fire heavy subsonic loads. The high penetration VKS round can penetrate up to 16 mm of steel at 200 m or body armor up to GOST 5A or NIJ III at 100 m. The accuracy of this cartridge when loaded with precision VKS bullets is claimed to be one MOA at 100 m up to the effective range limit of 690 m. Despite being chambered in the same cartridge, the ShAK-12 (and RSh-12) would not be able to feed or chamber rounds designed for the VKS due to significant length differences in the bullet component of the cartridge and thus requires its own, shorter, loads. The ShAK-12 rounds have less range compared to the VKS with the maximum effective range of the loads reaching in between 100 and 300 m.

• STs-130 (СЦ-130) - standard • STs-130PU (СЦ-130ПУ) - for training • STs-130PT (СЦ-130ПТ) - increased accuracy (59 gram bullet) • STs-130PT2 (СЦ-130ПТ2) - increased accuracy (solid bronze bullet) • STs-130VPS (СЦ-130ВПС) - increased penetration (76 gram bullet) The MTs-558 carbine, a civilian version of the VKS, is also designed for this full-length variant.

• Illustration — From left to right, light bullet, double-bulleted, heavy bullet, and armor-piercing bullet • PS-12 [ПС-12] Tyazhelaya Pulya (TP) or "Heavy Bullet" - Heavy subsonic lead bullet weighing 33 grams (509 grains). • PS-12A [ПС-12А] Legkaya Pulya (LP) or "Light Bullet" - Light supersonic lead bullet with an aluminum core weighing 7 grams (108 grains). • PS-12B [ПС-12Б] Broneboynaya Pulya (BP) or "Armor-Piercing Bullet" - Lead bullet with an armor-piercing component weighing nearly 18 grams (277 grains). • PD-12 [ПД-12] Dvukhpul'niy (DP) or "Double-Bulleted" - Two bullets loaded inline weighing 17 grams (262 grains) each. • STs-174 [СЦ-174]: civilian hunting load. Case headstamped 12.7x55 МЦ. For revolver carbine MTs-569, a civilian hunting version of the RSh-12.