7.92 x 57mm Mauser

7.92×57mm Mauser
From left to right 9.3×62 mm, .30-06 Springfield, 7.92×57mm IS, 6.5×55mm and 7.62×51mm NATO cartridges
Type	Rifle
Place of origin	Germany
Service history
In service	1905–present
Used by	Germany, United Kingdom, Spain, Czechoslovakia, Poland, Dominican Republic, Yugoslavia, The Ottoman Empire, Turkey, Iran, China, and other middle eastern countries
Wars	World War I, World War II and others
Production history
Designer	German Rifle Testing Commission
Designed	1904/1905
Variants	8×57mm IRS (rimmed)
Specifications
Parent case	M/88
Case type	Rimless, bottleneck
Bullet diameter	8.08 mm / .318 (I and IR) and 8.20 / .323" (IS and IRS)
Neck diameter	9.08 mm (0.357 in)
Shoulder diameter	10.95 mm (0.431 in)
Base diameter	11.94 mm (0.470 in)
Rim diameter	11.95 mm (0.470 in)
Rim thickness	1.30 mm (0.051 in)
Case length	57.00 mm (2.244 in)
Overall length	82.00 mm (3.228 in)
Case capacity	4.09 cm³ (63 gr H2O)
Rifling twist	240 mm (1 in 9.45 in)
Primer type	Large rifle
Maximum pressure	390 MPa (57,000 psi)
Ballistic performance
Bullet weight/type	Velocity	Energy
11.7 g (181 gr) RWS DK	820 m/s (2,700 ft/s)	3,934 J (2,902 ft·lbf)
12.1 g (187 gr) RWS HMK	820 m/s (2,700 ft/s)	4,068 J (3,000 ft·lbf)
12.7 g (196 gr) RWS TMR	800 m/s (2,600 ft/s)	4,064 J (2,997 ft·lbf)
12.8 g (198 gr) RWS ID Classic	800 m/s (2,600 ft/s)	4,096 J (3,021 ft·lbf)
Test barrel length: 600 mm (23.62 in) Source(s): RWS / RUAG Ammotech

The 7.92×57mm Mauser (designated as the 8mm Mauser or 8x57mm by the SAAMI and 8 x 57 IS by the C.I.P.) is a rimless bottlenecked rifle cartridge. The 7.92×57mm cartridge was adopted by the German Empire in 1905, and was the German service cartridge in both World Wars. IS stands for Infanterie, Spitz(geschoß) or "Infantry, Pointed (projectile)". Some sources list the letters "IS" as "JS", as capital letters I and J were interchangeable in abbreviations at this time.

The cartridge on which it was based was adopted by Germany in 1888 as the M/88 (along with the Gewehr 1888 service rifle. It was designed by the German Gewehr-Prüfungskommission (G.P.K.) ("Rifle Testing Commission") for the Gewehr 1888 and later used in Mauser bolt-action rifles, machine guns, and other ordnance weapons. The M/88 replaced the 11×60mm Mauser cartridge in German military service and marked Germany's switch from black powder to smokeless powder ammunition.

The 1905 pattern cartridge is currently (2012) known in the C.I.P. member states as the 8 × 57 IS (official C.I.P. designation) and in the United States of America as the 8mm Mauser or 8x57mm (SAAMI designations). The widespread use in German military Gewehr 98 and Karabiner 98k service rifles designed and manufactured by Mauser caused the "Mauser" tag, though Mauser had nothing to do with the development of this cartridge.

The British and Commonwealth forces used the 7.92×57mm Mauser cartridge in the BESA machine gun mounted on their armoured vehicles during World War II and referred to this ammunition like the U.S. military as 7.92(mm).

Development of the IS variant

The government-developed 7.92×57mm IS cartridge was a development of the M/88. The M/88 parent cartridge used a round-nosed bullet and was developed to be top-loaded into the magazine of the Gewehr 1888 rifle via an en bloc clip. The new 1905 pattern 7.92×57mm Mauser bullet was lighter, pointed, and 8.2 mm (0.323 in) in diameter instead of 8.08 mm (0.318 in). With the improved ballistic coefficient, the new IS cartridge had a flatter trajectory, and was therefore less critical of range estimation. It was used in rifles—like the Gewehr 98, Karabiner 98k, Gewehr 41, FG 42, or Gewehr 43—and in machine guns—like the MG 08, MG 34, or MG 42.

The rimless cartridge cases have been used as parent cases for several other necked down and necked up cartridges.

The rimmed variant, the 8×57mm IRS, was developed later for break-barrel rifles and combination guns.

Military use

Due to the cartridge's high performance and versatility it was adopted by the armed forces of various governments, including Spain, Poland, Czechoslovakia, Iran, Israel, Turkey, China, Egypt, former German African colonies, and the early Bundeswehr of West Germany. Its military use continues today in the former Yugoslavia in weapons like the Zastava M76 sniper rifle and the license-built copy of the MG 42, the SARAC M53 machine gun.

During World War II it was one of the few cartridges used by both the Axis and Allied powers, a distinction it shared with the 9×19mm Parabellum pistol round. Apart from being the standard rifle cartridge of the German armed forces, it was also used by the armed forces of Great Britain in the Besa machine gun, which was mounted in some of their tanks and other armoured vehicles—it was known as "Cartridge, SA, 7.92".

Civil use

7.92x57mm Mauser (above) and the rimmed 8×57mm IRS cartridges loaded with Brenneke TIG hunting bullets

The 7.92×57mm Mauser is a common chambering offering in rifles marketed for European sportsmen, alongside broadly similar cartridges such as the 5.6×57mm, 6.5×55mm, 6.5×57mm, and the 6.5×68mm and 8×68mm S magnum hunting cartridges. Major European manufacturers like Blaser, Česká Zbrojovka firearms, Heym, Mauser Jagdwaffen GmbH and Steyr Mannlicher produce factory new 7.92×57mm IS hunting rifles and European ammunition manufacturers like Blaser, RUAG Ammotec/RWS, Sako and Sellier & Bellot produce factory new ammunition. In 2004 Remington Arms offered a limited-edition Model 700 Classic bolt action hunting rifle chambered for the 7.92×57mm IS. The 7.92×57mm Mauser cartridge's performance is comparable to the American .30-06 Springfield cartridge and makes it suited in in Germay allowed for the hunting all large European game such as deer, chamois, mouflon, wild Boar and bears.

However, the 7.92x57mm Mauser cannot be used in countries which ban civil use of former or current military rifle cartridges, like France.

Beside the 7.92x57mm Mauser and 8×57mm I rimless rifle cartridges rimmed versions for break-action rifles also exist. The rimmed 8×57mm IRS and 8×57mm IR variants are offered as a chambering option in European break-action rifles.

Cartridge naming

German stripper clip with five 7.92×57mm IS cartridges for the Gewehr 98 and Karabiner 98k German rifles.

The modern descendant of the 1888 pattern of the M/88 cartridge is currently (2012) known in Europe as the 8 × 57 I (C.I.P. designation). Since the 8x57mm I and the rimmed 8x57mm IR and 8x57mm IRS cartridge variants were never issued to the military they were never named by English speaking sources like the military issued 7.92x57mm Mauser as 7.92 ammunition or the German military as 7.9 ammunition. Besides the 7.92x57mm Mauser and the also military issued 7.92x33mm Kurz no other cartridges originating from Germany having approximately 8 mm diameter were connected to the 7.92 mm naming, though there are much more rimless and rimmed 8 mm chamberings known and certified by the C.I.P.

European designations

The mainly European arms standards body Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives ("Permanent International Commission for portable firearms testing")—an organisation for standards in ammunition for civilian use—currently designates two 8 mm rimless cartridges of 57mm case length. Following the nomenclature of other European 8 mm cartyridge designs C.I.P. assigned the 8 × 57 I and 8 × 57 IS civil nomenclature to these cartridges. These designations currently (2012) have the power of law in C.I.P. member states like the United Kingdom.

U.S. designations

The United States standardizing body for sporting cartridges Sporting Arms and Ammunition Manufacturers' Institute (SAAMI) designates the 7.92×57mm Mauser cartridge as the 8mm Mauser, also known as 8×57mm.

The SAAMI (voluntary) pressure limitation for the 7.92×57mm Mauser cartridge is Piezo SAAMI Pmax = 241.317 MPa (35,000 psi) or 37,500 CUP. This is considerably lower than the C.I.P. pressure limit and is done for liability reasons, in case the 7.92×57mm IS cartridge is fired in an 'I' bore rifle that has a narrower throat and barrel diameter, to avoid catastrophic firearm failures that could endanger users or bystanders. Most European ammunition manufacturers generally only load to the lower pressure limit for "I" bore cartridges; and the US based manufacturer Hornady followed their lead in their (now discontinued) EuroSpec brand 8×57 JS load.

Other names and military designations

The military service cartridge is often designated by English speaking sources as 7.92x57mm or 7.92x57mm Mauser. This seems to be a persevering misnomer by English speaking sources and military historians. These designations were not used by either the C.I.P. or the SAAMI. The British Besa machine gun used in armored vehicles during World War II was chambered for the 7.92x57mm Mauser and the British referred to this ammunition as 7.92mm. US intelligence documents from World War II refer to the cartridge as 7.92 or 7.92 mm or 7.92-mm. The Germany military used 7,9 as designation or omitted any diameter reference and only printed the exact type of loading on ammunition boxes. Remarkably both the 7,9 and 7.92 in these designations do not exactly comply to the actual C.I.P. or SAAMI cartridge and bore dimensions.

The letter "J" often mentioned by English speaking sources is actually an "I" for Infanterie (German for "infantry"). A stamped "I" at the cartridge bottom in writing styles used in the past in Germany could be easily mistaken for a "J". Even in the 21st century the "I" is often substituted by a "J" in English speaking communities and German ammunition manufacturers often write "JS" instead of "IS" to avoid confusing customers. The letter "S" stands for Spitzgeschoß ("pointed bullet"), and the English word "spitzer" for that style of bullet is derived from this German term.

Cartridge drawings and dimensions

7.92×57mm IS

7.92×57mm Mauser maximum C.I.P. cartridge dimensions. All sizes in millimeters.

The 7.92×57mm IS cartridge has a cartridge case capacity of 4.09 ml (63 grains) H₂O. The exterior shape of the case was designed to promote reliable case feeding and extraction in bolt action rifles and machine guns alike, under extreme conditions.

Americans would define the shoulder angle at alpha/2 ≈ 19.1 degrees. The common rifling twist rate for this cartridge is 240 mm (1 in 9.45 in), 4 grooves, Ø of the lands = 7.89 mm, Ø grooves = 8.20 mm, land width = 4.40 mm and the primer type is large rifle.

According to the official C.I.P. guidelines the 7.92×57mm Mauser case can handle up to 390 MPa (56,564 psi) piezo pressure. In C.I.P. regulated countries every rifle cartridge combination has to be proofed at 125% of this maximum C.I.P. pressure to certify for sale to consumers.

8×57mm I

8×57mm I maximum C.I.P. cartridge dimensions. All sizes in millimeters.

The 8×57mm I was developed from the M/88 cartridge after the 7.92×57mm IS and was never in military use. Since these cartridges are lookalikes they can be easily mistaken for each other. The 8×57mm I cartridge has 4.03 ml (62 grains) H₂O cartridge case capacity. The exterior shape of the case was designed to promote reliable case feeding and extraction in bolt action rifles and machine guns alike, under extreme conditions.

Americans would define the shoulder angle at alpha/2 ≈ 19.1 degrees. The common rifling twist rate for this cartridge is 240 mm (1 in 9.45 in), 4 grooves, Ø lands = 7.80 mm, Ø grooves = 8.07 mm, land width = 4.40 mm and the primer type is large rifle.

According to the official C.I.P. guidelines the 8×57mm I case can handle up to 380 MPa (55114 psi) piezo pressure. In C.I.P. regulated countries every rifle and cartridge combination has to be proofed at 125% of this maximum C.I.P. pressure to certify for sale to consumers.

To avoid potentially serious accidents, it is important to distinguish clearly between these two not interchangable cartridges loaded for two differing chambers and bullet diameters, and only fire them in appropriately chambered/barrelled rifles.

German military ammunition

In 7.92×57mm caliber, "there were many German military versions of the cartridge, and Germany never stopped its development of different variations until the end" of World War II. "The bullet lengths varied a great deal through the different types, but all were loaded to an overall length" of 80.5 mm (3.17 in). The Germans had started using steel cases in World War I, "and by the end of 1943, most German ammunition had that type of case." The weights and case capacities of the Word War II military cartridge cases varied somewhat. The German military ammunition manufacturer Polte produced brass cartridge cases weighing 10.32 g (159 gr) with 4.03 ml (62 gr) H₂O case capacity and steel cartridge cases weighing 10.90 g (168 gr) with 3.95 ml (61 gr)H₂O case capacity.

German military standard ball evolution

Name	Year	Caliber	Bullet weight	Length	Rim	Base	Shoulder	Neck	OAL	Muzzle velocity	Muzzle energy
M/88	1888	8.07 mm (0.318 in)	14.6 g (226 gr)	57 mm (2.2 in)	11.95 mm (0.470 in)	11.94 mm (0.470 in)	10.95 mm (0.431 in)	8.99 mm (0.354 in)	80.5 mm (3.17 in)	639 m/s (2,100 ft/s)	2,983 joules (2,200 ft·lbf)
7.92×57mm IS	1905	8.2 mm (0.32 in)	9.9 g (154 gr)	57 mm (2.2 in)	11.95 mm (0.470 in)	11.94 mm (0.470 in)	10.95 mm (0.431 in)	9.08 mm (0.357 in)	80.5 mm (3.17 in)	878 m/s (2,880 ft/s)	3,857 joules (2,845 ft·lbf)
7.92×57mm IS	1934	8.2 mm (0.32 in)	12.8 g (197 gr)	57 mm (2.2 in)	11.95 mm (0.470 in)	11.94 mm (0.470 in)	10.95 mm (0.431 in)	9.08 mm (0.357 in)	80.5 mm (3.17 in)	760 m/s (2,500 ft/s)	3,697 joules (2,727 ft·lbf)
The data for the M/88 and the 7.92×57mm IS of 1905 is for Gewehr 98 rifles with 740 mm (29 in) barrel length. The data for the 8×57mm IS of 1934 is for Karabiner 98k rifles with 600 mm (24 in) barrel length.

German cartridge variants during World War II

German 7.92 mm sS 12.8 g (198 gr) Full Metal Jacket Boat-Tail round.

1941 steel cased German ball ammunition. 7.92x57IS

Spitzgeschoß mit Kern, yellow bullet, red circular cap groove

The German standard sS (schweres Spitzgeschoß—"heavy pointed bullet") ball bullet was 35.3 mm (1.39 in) long, boat-tailed, and very well made. It was lead filled, had a gilding-metal-plated jacket, and weighed 12.8 grams (198 gr). It 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). 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 sS 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). Even by contemporary (2010) standards 1000⁺ m (1,094⁺ yards) effective 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.

During World War II German snipers were issued with purpose manufactured sniping ammunition, known as the 'effect-firing' sS round. The 'effect-firing' sS round featured an extra carefully measured propellant charge and seated a sS full metal jacketed boat tail projectile of match grade build quality, lacking usual features such as a seating ring or cannelure to further improve the already high ballistic coefficient.

Special ammunition included:

• SmK L'spur - Leuchtspur (SmK tracer)—red circular groove, black bullet point

German tracer bullets "were the best put out by any country — streamlined and with excellent ballistics".

• SmK-Geschoß - Spitzgeschoß mit Kern ("Spitzer with Core")—steel cored projectile for use against targets behind thick covers, tanks, or airplanes. Red circular cap groove, yellow bullet. There was also a version with a black projectile which had a tungsten carbide instead of a steel core.

German Spitzgeschoss mit Kern armor-piercing bullets were also very good, being very stable and accurate at long ranges. The most common type of armor-piercing round had a hardened-steel core with plated-steel jacket and weighed 11.5 grams (177 gr). Other types appeared which used tungsten carbide and combinations for cores. Sintered iron and mild steel cores also came into use in ball ammunition.

• PmK-Geschoß - (Phosphor mit Stahlkern) ("phosphorus with steel core") German Luftwaffe (Air force) 7.9 mm high velocity machine gun ammunition loaded with the 10.15 grams (156.6 gr) PmK (Phosphor mit Stahlkern—"phosphorus with steel core") ball bullets, featuring a higher muzzle velocity than standard ammunition due to a more powerful smokeless powder charge. These rounds were designated as V-patronen, with 'V' being short for improved (German: verbessert). This cartridge can be recognised by the black circular cap groove, yellow bullet.
• B-Geschoß - (Beobachtung) ("observation") — The German Luftwaffe 10.85 grams (167.4 gr) B (Beobachtung—"observation") HE incendiary ball bullets contained phosphorus and "had a pellet in it which exploded on contact with any target, however frail". The B ball bullet was like any other high-explosive or incendiary bullet, illegal for anti-personnel use according to the Hague Conventions. It featured a higher muzzle velocity than standard ammunition due to a more powerful smokeless powder charge. These rounds were designated as V-patronen, with 'V' being short for improved (German: verbessert). "The Germans maintained that it was used mainly for observation and range-finding, but observers report having seen them in rifle clips and machine gun belts". The regular German infantry units were not allowed to use this round; however German snipers sometimes used this high velocity round to gain an extra 100 m (110 yards) effective range and cause horrendous wounds. The standard issue Karabiner 98k rifles handled these higher pressure cartridges without issues. This cartridge can be recognised by the black circular cap groove, yellow bullet.
• SPr-Geschoß - S-Phosphor (S incendiary)—black circular groove, clear or black bullet
• Platzpatrone (blank cartridge)—two cannelures in the brass, red wood- or cardboard-bullet, cardboard plug (Fließpappe-Pfropfen) between bullet and propellant powder. Safe distance given at 25m.
• Exerzierpatrone ("drill cartridge")—two variants:
  • S-Punkt ("S-dot") with vertical grooves in the brass for aiming exercises.
  • Werkzeug ("tool") with the same weight as a sS ball cartridge for examining the functioning of firearms action. A horizontal ring of small holes above the extractor grooves differentiated the Werkzeug round from the sS ball cartridge.

British military ammunition

British cartridges included "Ball", "Armour-Piercing", "Tracer", and "Incendiary". Blanks and a Drill round were also available for instruction purposes. The Drill round was an aluminium bullet fixed in a chromium-plated case which had three deep lengthwise recesses painted red to identify it. Ammunition was supplied in belted form with 225 rounds per belt.

Designation	Marks	Annulus colour	Notes
Cartridge, SA, Ball, 7.92mm	Mark I.Z, Mark II.Z	Dark purple if present	Mark II.Z bullet has "flatter" nose and longer parallel portion to engage with rifling
Cartridge, SA, Armour-piercing, 7.92mm	Mark I.Z, Mark II.Z	Green	Hard steel core, lead-antimony sleeve, steel envelope
Cartridge, SA, Tracer, 7.92mm	Mark I.Z, Mark II.Z	Red	Red tracer composition in non-streamlined bullet. Effective for 900 yards.
Cartridge, SA, Incendiary, 7.92mm	Mark I	Blue

The Ball case was filled with a charge of around 45 grains of nitro-cellulose.

The British cartridge was used in only one weapon—the "7.92mm BESA machine gun". This was a Czech design adopted shortly before the war as a move towards rimless ammunition across the armed service. However the move was disrupted by the lead up to war. The BESA was only fitted to tanks and armoured cars of British design (the original Czech design was also produced for German use following the occupation of Czechoslovakia) and captured German ammunition was used when available.

8mm cartridges compared

Maximum muzzle velocity comparison in %

Bullet weight gram (grain)	8.23 g (127 gr)	9.72 g (150 gr)	11.34 g (175 gr)	12.96 g (200 gr)	14.26 g (220 gr)	Case capacity (%)
7.92×57mm IS	100.0	100.0	100.0	100.0	100.0	100.0
8×64mm S	102.7	102.7	102.8	102.9	102.9	110.3
.325 WSM	108.7	109.1	109.0	109.3	111.1	131.7
8×68mm S	108.4	108.5	108.7	110.5	112.3	136.5
8mm Rem. Mag.	111.9	112.3	114.5	115.3	116.0	157.1
Using the probably most proliferated European and American 8 mm rifle cartridges out of 650 mm (25.59 in) long barrels loaded with relatively light to heavy 8 mm bullets to their C.I.P. or SAAMI (Sporting Arms and Ammunition Manufacturers’ Institute) sanctioned maximum pressures.[citation needed]

This comparison is not totally objective since the 8mm Remington Magnum and .325 WSM operate at 448.16 MPa (65000 psi), the 8×68mm S at 440 MPa (63817 psi), the 8×64mm S at 405 MPa (58740 psi) and the 7.92×57mm Mauser at 390 MPa (56564 psi) maximum chamber pressure. Higher chamber pressure results in higher muzzle velocities.

The 7.92 x 57mm Mauser as parent case

This was the parent case for many other later cartridges, such as:

• 5.6×57mm
• 6×57mm Triebel (wildcat)
• 6.5x57mm
• 9×57mm Mauser
• 9.3×57mm see 9×57mm Mauser article
• 10×57mm
• 10.5×57mm

See also

• List of rifle cartridges
• 8mm caliber
• 7.92x33mm Kurz

Contemporary military rifle cartridges

• 7.62×54mmR
• 8mm Lebel
• .303 British
• .30-06 Springfield

References

• WOUND BALLISTICS, Medical Department United States Army in World War II
• C.I.P. CD-ROM edition 2003
• C.I.P. decisions, texts and tables

External links

• The german Mauser K98k Info site
• The Mauser Shooting Association
• Munition 7,9×57 IS / 7,9×57
• Various images of 7,92×57mm Mauser cartridges
• Technical drawings of German 8×57 IS bullet types
• 7,92 Mauser WWII (Italian)
• 7,92×57 on GunsTribune
• RIFLE AND MACHINE-GUN AMMUNITION (7.92mm) US Military Intelligence Service, Special Series No. 14, May 25, 1943
• The 8mm (7,92×57) Mauser Cartridge
• British produced 7.92mm BESA ammunition