Some further reading.
https://www.thehighroad.org/index.php?threads/8x57-mauser-max-cup-for-reloading.594648/
German cartridge variants during World War II
Karabiner 98k stripper clip with brass-cased 7.92×57mm ammunition
German 7.92 mm s.S. 12.8 g (198 gr) Full Metal Jacket Boat-Tail round.
Steel lacquered cased German s.S. ball ammunition produced in 1941.
Spitzgeschoß mit Kern, yellow bullet, red circular cap groove
The German standard
s.S. - schweres Spitzgeschoß ("heavy pointed or spitzer bullet") ball bullet cartridge was originally designed for long range machine gun use and was 35.3 mm (1.39 in) long, boat-tailed, and very well made.
[19][23] It was lead filled, had a gilding-metal-plated jacket, and weighed 12.8 grams (197.53 gr). The
s.S. Patrone had a muzzle velocity of 760 m/s (2,493 ft/s) and an operating pressure of 320 MPa (46,412 psi). From its 1914 introduction the
s.S. Patrone was mainly issued for aerial combat and as of 1918 in the later stages of World War I to infantry machine gunners. The desire for adapting new shorter barreled rifles and introduction of the Karabiner 98k were reasons for changing the standard German service ball rifle cartridge. The 1903 pattern 7.92×57mm Mauser
S Patrone produced excessive muzzle flash when fired from arms that did not have a long barrel like the Gewehr 98. It was found that the
s.S. Patrone, originally designed for long range machine gun use, produced less muzzle flash out of rifles that had a less long barrel and also provided better accuracy. Because of this the
S Patrone was phased out in 1933 and the
s.S. Patrone became the standard German service ball cartridge in the 1930s when the German rearmament program started.
[24][25] The s.S. ball
boat tail projectile was designed for long range use and offered the best aerodynamic efficiency and external ballistic performance of any standard rifle bullet used during World War II, with a G1
ballistic coefficient between 0.593 and 0.557 (ballistic coefficients are somewhat debatable) or a ballistic coefficient of approximately 0.295 (G7). When fired at the typical muzzle velocity of 760 m/s (2,493 ft/s) out of a 600 mm (23.6 in) barrel the s.S. bullet retained
supersonic velocity up to and past 1,000 m (1,094 yd) (V1000 ≈
Mach 1.07) under
International Standard Atmosphere conditions at sea level (
air density ρ = 1.225 kg/m3). It had a maximum range of approximately 4,700 m (5,140 yd)
[21] Even by contemporary (2012) standards 1000+ m (1,094+ yards) effective supersonic range is quite remarkable for a standard military rifle round. For recognition the circular groove between cap and brass was green, and it had a yellow colored bullet.
The regular s.S. projectile had the following penetration performance: 85 cm (33 in) of dry pine wood at 100 m (109 yd), 65 cm (26 in) at 400 m (437 yd), 45 cm (18 in) at 800 m (875 yd) and 10 cm (4 in) at 1,800 m (1,969 yd), 10 mm (0.39 in) of iron at 300 m (328 yd), 7 mm (0.28 in) at 550 m (601 yd), 5 mm (0.20 in) of steel at 100 m (109 yd) and 3 mm (0.12 in) at 600 m (656 yd).
During World War II German snipers were issued with purpose-manufactured sniping ammunition, known as the 'effect-firing' s.S. round.
[26] The 'effect-firing' s.S. round featured an extra carefully measured propellant charge and seated an sS full-metal-jacketed boat-tail projectile of match-grade build quality, lacking usual features such as a cannelure to further improve the already high G1 ballistic coefficient to approximately 0.595 (G1) or 0.300 (G7).
[27] The 'effect-firing' s.S. projectile had a form factor (G7
i) of 0.869, which indicates good aerodynamic efficiency and external ballistic performance for the bullet diameter.
[28][29]
Special ammunition included:
[20][30][31]
- S.m.K. - Spitzgeschoß mit Kern ("spitzer with core") — hardened steel cored projectile for use against targets behind thick covers, tanks, or airplanes. Red circular cap groove, yellow bullet, bullet weight 11.85 g (182.9 gr), muzzle velocity 785 m/s (2,575 ft/s), operating pressure 300 MPa (43,511 psi). This ammunition was also produced in a S.m.K.-v high-velocity or "v" ammunition variant that added 100 m/s (328 ft/s) muzzle velocity to the normal S.m.K. variant.[32] There was also a version S.m.K.H. - Spitzgeschoß mit Hartkern ("spitzer with hardcore") which had a tungsten carbide instead of a steel core. Sintered iron and mild steel cores also came into use in this ammunition. German Spitzgeschoss mit Kern armor-piercing bullets were very good, being very stable and accurate at long ranges.[19]
- S.m.K. L'spur - Spitzgeschoß mit Kern Leuchtspur ("spitzer with core tracer") — red circular groove, black bullet point—German tracer bullets "were the best put out by any country — streamlined and with excellent ballistics".[19] The bullet was basically the same as used in the S.m.K. ammunition but combined with a tracer that burned for 800 to 1,000 m (875 to 1,094 yd). It had a bullet weight of 10.00 g (154.3 gr) and a muzzle velocity of 810 m/s (2,657 ft/s) and an operating pressure of 280 MPa (40,611 psi). This ammunition was also produced in a S.m.K. L'spur-v high-velocity or "v" ammunition variant that added 115 m/s (377 ft/s) muzzle velocity to the normal S.m.K. L'spur variant.[32] These rounds were also available in 'S.m.K. L'spur 100/600' and S.m.K. L'spur-v 100/600 variants for aerial use that burned between 100 and 600 m (109 and 656 yd).
- S.m.K. Gl'spur - Spitzgeschoß mit Kern Glimmspur ("spitzer with core night tracer" )— red circular groove, black bullet point—German night tracer bullets. The bullet was basically the same as used in the S.m.K. ammunition but combined with a dimmed tracer that was visible from 150 m (164 yd) to 800 to 1,000 m (875 to 1,094 yd) and would not temporarily blind dark adapted eyes in low light conditions. It had a bullet weight of 10.00 g (154.3 gr) and a muzzle velocity of 810 m/s (2,657 ft/s) and an operating pressure of 280 MPa (40,611 psi). This ammunition was also produced in a S.m.K. Gl'spur-v high-velocity or "v" ammunition variant that added 115 m/s (377 ft/s) muzzle velocity to the normal S.m.K. Gl'spur variant.[32] These rounds were also available in S.m.K. Gl'spur 100/600 and S.m.K. Gl'spur-v 100/600 variants for aerial use that burned between 100 and 600 m (109 and 656 yd).
- P.m.K. - Phosphor mit Kern ("phosphorus with steel core") machine gun ammunition loaded with the 10.15 grams (156.6 gr) P.m.K. bullets that had a muzzle velocity of 830 m/s (2,723 ft/s) and an operating pressure of 280 MPa (40,611 psi). This cartridge can be recognised by the black circular cap groove, yellow bullet. This ammunition was also produced in a P.m.K.-v high-velocity or "v" ammunition variant that added 115 m/s (377 ft/s) muzzle velocity to the normal P.m.K. variant.[32]
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