Engineering:7.62×54mmR

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Short description: Russian military rifle cartridge
7.62×54mmR
76254Rvariety.jpg
Examples of 7.62×54mmR rimmed ammunition. The photo shows, reading from left to right: Sellier & Bellot hollow point boat tail; "Czech silver tip", mild steel core, light ball; Hungarian silver/yellow-tip, mild steel core, heavy ball; Wolf Ammunition gold soft-point; USSR 1986 steel core light ball, Factory 60. [1]; Yugoslav surplus (1953); USSR 1940s lead core light ball [2]
TypeRifle
Place of originRussian Empire
Service history
In service1891–present
Used by
Wars
  • Boxer Rebellion
  • Russo-Japanese War
  • World War I
  • Russian Civil War
  • Soviet–Japanese border conflicts
  • Winter War
  • World War II
  • Korean War
  • Vietnam War
  • Laotian Civil War
  • Cambodian Civil War
  • Cambodian–Vietnamese War
  • Soviet–Afghan War
  • Iran-Iraq War
  • Yugoslav wars
  • First Chechen War
  • Gulf War
  • Second Chechen War
  • War in Afghanistan (2001-2021)
  • Iraq War
  • Cambodian–Thai border dispute
  • Russia–Georgia war
  • Libyan Civil War
  • Syrian civil war
  • Yemeni Civil War (2015–present)
  • Saudi Arabian-led intervention in Yemen
  • Russo-Ukrainian War
  • Others Wars
Production history
DesignerColonel N. F. Rogovtsev
Designed1891
Produced1891–present
Specifications
Case typeRimmed, bottleneck
Bullet diameter7.92 mm (0.312 in)
Neck diameter8.53 mm (0.336 in)
Shoulder diameter11.61 mm (0.457 in)
Base diameter12.37 mm (0.487 in)
Rim diameter14.48 mm (0.570 in)
Rim thickness1.60 mm (0.063 in)
Case length53.72 mm (2.115 in)
Overall length77.16 mm (3.038 in)
Case capacity4.16 cm3 (64.2 gr H2O)
Rifling twist240 mm (1 in 9.45 in)
Primer typeBerdan or boxer large rifle
Maximum pressure390.00 MPa (56,565 psi)
Ballistic performance
Bullet mass/type Velocity Energy
11.3 g (174 gr) HPBT 797 m/s (2,610 ft/s) 3,593 J (2,650 ft⋅lbf)
11.7 g (181 gr) FMJ 786 m/s (2,580 ft/s) 3,614 J (2,666 ft⋅lbf)
11.7 g (181 gr) SP 800 m/s (2,600 ft/s) 3,744 J (2,761 ft⋅lbf)
9.7 g (150 gr) FMJ 865 m/s (2,840 ft/s) 3,629 J (2,677 ft⋅lbf)
11.7 g (181 gr) SP 805 m/s (2,640 ft/s) 3,779 J (2,787 ft⋅lbf)
Test barrel length: 73 cm (28 in)
Source(s): [2][3]
Soviet World War II era service cartridges: (Left to right) 7.62×54mmR, 7.62×39mm, 7.62×25mm
Modern service rifle cartridge cases: (Left to right) 7.62×54mmR, 7.62×51mm NATO, 7.62×39mm, 5.56×45mm NATO, 5.45×39mm

The 7.62×54mmR is a rimmed rifle cartridge developed by the Russian Empire and introduced as a service cartridge in 1891. Originally designed for the bolt-action Mosin–Nagant rifle, it was used during the late tsarist era and throughout the Soviet period to the present day. The cartridge remains one of the few standard-issue rimmed cartridges still in military use, and has one of the longest service lives of any military-issued cartridge.[4]

The fully-powered 7.62×54mmR cartridge is still in use by the Russian military in the Dragunov, SV-98 and other sniper rifles, as well as some modern general-purpose machine guns like the PKM and Pecheneg machine gun. Originally, the round was designated "Трехлинейный патрон образца 1891 года" – (three-line cartridge model of 1891). It then became widely known under the designation "7,62мм винтовочный патрон" (7.62 mm rifle cartridge). The round has erroneously come to be known as the "7.62mm Russian" (and is still often referred to as such colloquially), but, according to standards, the R in designation (7.62×54mmR) stands for "rimmed", in line with standard C.I.P. designations. The name is sometimes confused with the "7.62 Soviet" round, which refers to the rimless 7.62×39mm intermediate cartridge used in the SKS and AK-based (AK-47, RPK) rifles and light machine gun.

Background

The 7.62×54mmR is the second-oldest cartridge still in regular combat service with several major armed forces in the world.[citation needed] It is second to the .303 British which entered military service in 1889 and remains in service,[citation needed] primarily in some noncombatant Commonwealth nations around the world.[citation needed] In 2021, the cartridge reached 130 years in service. (As of December 2013) the 7.62×54mmR is mainly used in designated marksman and sniper rifles like the Dragunov sniper rifle, SV-98 and machine guns like the PKM. It is also one of the few (along with the .22 Hornet, .30-30 Winchester, and .303 British) bottlenecked, rimmed centerfire rifle cartridges still in common use today. Most of the bottleneck rimmed cartridges of the late 1880s and 1890s fell into disuse by the end of the First World War.[citation needed]

The .30-06 Springfield cartridge (7.62×63 mm), with its higher service pressure and case capacity, will outperform the 7.62×54mmR when same-length test barrels are used, though this is very uncommon as .30-06 Springfield firearms are generally sold with much shorter barrels than 7.62×54mmR firearms.[5] Commonly available 7.62×54mmR 150 gr (9.7 g) commercial ammunition chronographs around 3,000 ft/s (914 m/s) from the typical Mosin-Nagant (29") barrel, while the heavier 180 gr (11.7 g) loads chonograph in the low 2,700 ft/s (823 m/s) range. This is identical to .30-06 Springfield performance from a 24" barrel and slightly better than .30-06 Springfield performance from a 22-inch barrel.[citation needed]

The 7.62×54mmR originally had a 13.7 g (210 grain) "jager" round-nosed full metal jacket (FMJ) bullet. The projectile was replaced in 1908 by the 9.61-gram (148.3 gr) Лёгкая Пуля (Lyogkaya pulya, "light bullet") spitzer bullet, whose basic design has remained to the present. The Lyogkaya pulya, or L-bullet, had a ballistic coefficient (G1 BC) of approximately 0.338 and (G7 BC) of approximately 0.185.[citation needed]

Sniper rounds

To increase accuracy for the Dragunov SVD, the Soviets developed the 7N1 variant of the cartridge in 1966. The 7N1 was developed by V. M. Sabelnikov, P. P. Sazonov and V. M. Dvorianinov. It used match-grade extruded powder instead of the coarser ball propellant and had a 9.8 g (151.2 gr) boat-tailed FMJ jacketed projectile with an air pocket, a steel core and a lead knocker in the base for maximum terminal effect. It had a ballistic coefficient (G1 BC) of approximately 0.411 and (G7 BC) of approximately 0.206. Produced by "Factory 188" (Novosibirsk Low Voltage Equipment Plant), cartridges are only head-stamped with the number "188" and the year of manufacture. It came packaged 20 loose rounds to a paper packet, 22 packets to a metal "spam" tin, and two tins per wooden case for a total of 880 rounds. The individual paper packets, hermetically sealed metal 'spam' cans, and wooden shipping crates were all distinctly marked Снайперская (Snaiperskaya, the adjective form of "sniper"). Even the wax wrapping paper for the paper packets was covered in red text to make sure it was not misused.[citation needed]

As hard body armor saw increasing use in militaries, the 7N1 was replaced in 1999 by the 7N14 special load developed for the SVD. The 7N14 round is loaded with a 9.8 g (151.2 gr) projectile containing a sharp hardened steel penetrator to improve penetration which is fired with an average muzzle velocity of 830 m/s (2,723 ft/s), for a muzzle energy of 3,375 J (2,489 ft⋅lbf).[citation needed]

Cartridge dimensions

The 7.62×54mmR has 4.16 ml (64 grain 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 challenging conditions.

7.62 x 54 R cartridge.svg

7.62×54mmR maximum C.I.P. cartridge dimensions. All sizes in millimeters (mm).[6]

Americans would define the shoulder angle at alpha/2 ≈ 18.5 degrees. The common rifling twist rate for this cartridge is 240 mm (1 in 9.45 in), 4 grooves, Ø lands = 7.62 mm (0.300 in), Ø grooves = 7.92 mm (0.312 in), land width = 3.81 mm and the primer type is Berdan or very rarely Boxer (in large rifle size).

According to the official C.I.P. (Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives) rulings the 7.62×54mmR can handle up to 390.00 MPa (56,565 psi) Pmax piezo pressure. In C.I.P. regulated countries every rifle cartridge combo has to be proofed at 125% of this maximum C.I.P. pressure to certify for sale to consumers. This means that 7.62×54mmR chambered arms in C.I.P.-regulated countries are currently (2014) proof tested at 487.50 MPa (70,706 psi) PE piezo pressure.

Performance

The attainable muzzle velocities and muzzle energies of the 7.62×54mmR are comparable with standard 7.62×51mm NATO cartridges. However, a rimmed case such as the one used in the 7.62×54mmR cartridge can complicate smooth feeding within box magazines, but they are by no means unreliable.[7]

When used with modern hunting bullets, the 7.62×54mmR is capable of taking game in the medium- to large-sized class (CXP2 and CXP3). The 7.62×54mmR can offer very good penetrating ability due to a fast twist rate that enables it to fire long, heavy bullets with a high sectional density. In Russia, the 7.62×54mmR is commonly used for hunting purposes, mostly in sporterized Mosin–Nagant rifles and civil Dragunov variants (Tigers).

Basic specifications of 21st century Russian service loads

From left to right: L type bullet with lead core, LPS bullet with steel core aside, green tip T-46M tracer with tracer cup (opened both at top and bottom) and lead tip aside, T-46 tracer with extended cup (opened only at the bottom). All bullet jackets and tracer cups are made from copper washed steel.

The 7.62×54mmR rounds in use with the Russian Armed Forces are designed for machine guns and sniper rifles. As of 2003, there were several variants of 7.62×54mmR rounds produced for various purposes. All use clad metal as case material.

57-N-323S
A conventional steel-core bullet designed to engage personnel and weapon systems. The bullet has a steel core and has a ballistic coefficient (G1 BC) of approximately 0.374 and (G7 BC) of approximately 0.187. The tip has no distinguishing colour. It can penetrate a 6 mm (0.2 in) thick St3 steel plate at 520 m (569 yd) and 6Zh85T body armor at 110 m (120 yd).
7N13
An enhanced-penetration bullet designed to kill personnel wearing body armor, featuring a heat-strengthened core. The tip is uncoloured. A sealing lacquer belt on the mouth of the case is red-coloured. It can penetrate a 6 mm (0.2 in) thick St3 steel plate at 660 m (722 yd) and 6Zh85T body armor at 800 m (875 yd).
7T2
A variant of the T-46, a tracer bullet designed for fire adjustment and target designation. The bullet has a green tip, and the tracer burns for 3 seconds.
7BZ3
A variant of the B-32, an armor-piercing/incendiary bullet designed to defeat lightly armored targets. The bullet has a black-red tip.
7N1
A sniper round designed for improved accuracy. The tip of the bullet is uncoloured.
Cartridge designation[8][9]
57-N-323S 7N13 (AP) 7T2 (tracer) 7BZ3 (API) 7N1 (sniper load)
Cartridge weight 21.8 g (336 gr) 21.7 g (335 gr) 22 g (340 gr) 22.6 g (349 gr) 21.9 g (338 gr)
Bullet weight 9.6 g (148.2 gr) 9.4 g (145.1 gr) 9.65 g (148.9 gr) 10.39 g (160.3 gr) 9.8 g (151.2 gr)
Muzzle velocity 828 m/s (2,717 ft/s) 828 m/s (2,717 ft/s) 798 m/s (2,618 ft/s) 809 m/s (2,654 ft/s) 823 m/s (2,700 ft/s)
Muzzle energy 3,291 J (2,427 ft⋅lbf) 3,222 J (2,376 ft⋅lbf) 3,073 J (2,267 ft⋅lbf) 3,400 J (2,508 ft⋅lbf) 3,319 J (2,448 ft⋅lbf)
Accuracy of fire at
300 m (328 yd)
90 mm (3.5 in) (R50) 90 mm (3.5 in) (R50) 150 mm (5.9 in) (R50) 150 mm (5.9 in) (R50) 80 mm (3.1 in) (R100)
  • R50 at 300 m (328 yd) means the closest 50% of the shot group will all be within a circle of the mentioned diameter at 300 m (328 yd).
  • R100 at 300 m (328 yd) means every shot of the shot group will be within a circle of the mentioned diameter at 300 m (328 yd).

Availability

7.62×54mmR is widely available both as military surplus and new production, but less so for match-grade rounds. Most surplus ammunition is steel-cased and uses Berdan primers, which effectively hinders its use for handloading. However, with the increased popularity of surplus Eastern-bloc Mosin–Nagant, SVT-40, and PSL rifles in the United States, Boxer-primed ammunition and unfired cases are increasingly available; these cases take large rifle primers.

Cartridge derivatives

USSR/Russia

  • 6.5×54mmR: necked-down version, used in both converted Mosin biathlon rifles and Vostok-brand biathlon rifles in the 1960s and 1970.[10]
  • 9×53mmR: hunting cartridge.
  • 9.6×53mmR Lancaster: hunting cartridge.[11]

Finland

  • 7.62×53mmR: military cartridge. Considered identical to 7.62×54mmR by some manufacturers, but not by CIP.
  • 8.2×53mmR: hunting cartridge.[12]
  • 9.3×53mmR: hunting cartridge.[13]

List of 7.62×54mmR firearms

Alternative names

While the only official nomenclature for the cartridge is 7.62x54R ("R" standing for "rimmed"), some shooters in the U.S. have confused the "R" as an abbreviation for "Russian" due to the rounds' origin.

  • 7.62×54R
  • 7.62 Russian
  • 7.62 Mosin–Nagant
  • 7.62 Dragunov
  • 7.62 M91
  • .30 Russian[14]
  • Rimmed Russian

See also

References

Notes

Bibliography

External links