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In the 1960s Yugoslavia experimented with new bullet designs to produce a round with a superior wounding profile, speed, and accuracy to the M43. The M67 projectile is shorter and flatter-based than the M43. This is mainly due to the deletion of the mild steel insert. This has the side effect of shifting the center of gravity rearward in comparison to the M43. This allows the projectile to destabilize nearly {{convert|17|cm|in|abbr=on}}<ref name="uthr.org"/> earlier in tissue. This causes a pair of large stretch cavities at a depth likely to cause effective wound trauma. When the temporary stretch cavity intersects with the skin at the exit area, a larger exit wound will result, which takes longer to heal. Additionally, when the stretch cavity intersects a stiff organ like the liver, it will cause damage to that organ.
In the 1960s Yugoslavia experimented with new bullet designs to produce a round with a superior wounding profile, speed, and accuracy to the M43. The M67 projectile is shorter and flatter-based than the M43. This is mainly due to the deletion of the mild steel insert. This has the side effect of shifting the center of gravity rearward in comparison to the M43. This allows the projectile to destabilize nearly {{convert|17|cm|in|abbr=on}}<ref name="uthr.org"/> earlier in tissue. This causes a pair of large stretch cavities at a depth likely to cause effective wound trauma. When the temporary stretch cavity intersects with the skin at the exit area, a larger exit wound will result, which takes longer to heal. Additionally, when the stretch cavity intersects a stiff organ like the liver, it will cause damage to that organ.


The wounding potential of M67 is mostly limited to the small permanent wound channel the bullet itself makes.<ref name="uthr.org"/> The real damage of the M67 occurs when it yaws.<ref name="uthr.org"/> Meanwhile a fragmenting round (like the [[5.56×45mm NATO]]) might cause massive tissue trauma and blood loss (and thus rapid incapacitation) on a lung or abdominal hit, the M67 has a greater chance of merely wounding the target. However, the 5.56×45mm will only reliably fragment in close ranges below {{convert|125|m|ft|lk=on|abbr=off}}.{{Citation needed|date=March 2009}}
The wounding potential of M67 is mostly limited to the small permanent wound channel the bullet itself makes.<ref name="uthr.org"/> The real damage of the M67 occurs when it yaws.<ref name="uthr.org"/> Meanwhile a fragmenting round (like the [[5.56×45mm NATO]]) might cause massive tissue trauma and blood loss (and thus rapid incapacitation) on a lung or abdominal hit, the M67 has a greater chance of merely wounding the target.{{citation needed|date=Aug 2012}} However, the 5.56×45mm will only reliably fragment in close ranges below {{convert|125|m|ft|lk=on|abbr=off}}.{{Citation needed|date=March 2009}}


Many contemporary Russian-made 7.62×39 cartridges, such as those sold under the brand names [[Wolf Ammunition]] and Golden Tiger, feature a modified M67 bullet with an airspace cast into the nose, or similar ballistic-enhancing tip design (e.g. 8m3), which improves fragmentation and/or tumbling tendencies.
Many contemporary Russian-made 7.62×39 cartridges, such as those sold under the brand names [[Wolf Ammunition]] and Golden Tiger, feature a modified M67 bullet with an airspace cast into the nose, or similar ballistic-enhancing tip design (e.g. 8m3), which improves fragmentation and/or tumbling tendencies.

Revision as of 22:54, 26 August 2012

7.62×39mm
Lateral view of a steel-cased 7.62×39mm FMJ cartridge.
TypeRifle
Place of origin Soviet Union
Service history
In service1944–present
Used bySoviet Union, former Warsaw Pact, People's Republic of China, Cambodia, North Korea, Vietnam, Finland, Venezuela, many others
Production history
Designed1943
Produced1943–present
Specifications
Case typeRimless, bottleneck
Bullet diameter7.92 mm (0.312 in)
Neck diameter8.60 mm (0.339 in)
Shoulder diameter10.07 mm (0.396 in)
Base diameter11.35 mm (0.447 in)
Rim diameter11.35 mm (0.447 in)
Rim thickness1.50 mm (0.059 in)
Case length38.70 mm (1.524 in)
Overall length56.00 mm (2.205 in)
Case capacity2.31 cm3 (35.6 gr H2O)
Rifling twist240 mm (1 in 9.45 in)
Primer typeBoxer Large Rifle
Maximum pressure355.00 MPa (51,488 psi)
FillingSSNF 50 powder
Filling weight18.21 gr
Ballistic performance
Bullet mass/type Velocity Energy
123 gr (8 g) Full metal jacket 731.5 m/s (2,400 ft/s) 2,073.6 J (1,529.4 ft⋅lbf)
154 gr (10 g) Spitzer SP 641.3 m/s (2,104 ft/s) 2,056.3 J (1,516.6 ft⋅lbf)
123.5 gr (8 g) Full metal jacket 804.7 m/s (2,640 ft/s) 2,460 J (1,810 ft⋅lbf)
123 gr (8 g) Full metal jacket 738 m/s (2,420 ft/s) 2,179 J (1,607 ft⋅lbf)
Test barrel length: 415 mm
Source(s): Wolf Ammo[1] Omar [2] Sellier & Bellot [3]

The 7.62×39mm round is a rifle cartridge of Soviet origin that was designed during World War II. It was first used in the RPD machine gun. Due to the worldwide proliferation of the SKS-45 and AK-47 pattern rifles, the cartridge is utilized by both militaries and civilians alike. 7.62×39mm ammunition is purportedly tested to function well in temperatures ranging from −50 °C (−58 °F) to 50 °C (122 °F) cementing its usefulness in extremely cold polar or hot desert conditions.

The 7.62×39mm cartridge was likely influenced by a variety of foreign developments, especially the pre-war German GeCo, 7.75×39mm experimental round,[4] and its developements in the German late-war Intermediate cartridge trials in calibers 7.9mm and 7.62mm. The German adopted 7.92×33mm Kurz by Polte did not influence developement.

Shortly after the war, the world's most recognized military pattern rifle was designed for this cartridge: the AK-47. The cartridge remained the Soviet standard until the 1970s, and is still one of the most common intermediate rifle cartridges used around the world. It was replaced in Russian service by the 5.45×39mm cartridge, which is used by the current issue AK-74 and variants.

The 7.62×39mm cartridge produces significant wounding if the bullet tumbles in tissue,[5] but produces relatively minor wounds in cases where the bullet exits before beginning to yaw or does not yaw.[6][7] In the absence of yaw, the M43 load can pencil through lung tissue with relatively little injury.[8]

History

Oblique view of a steel-cased 7.62×39mm FMJ cartridge.
7.62×39 shown along side other cartridges. From left to right: .30-06 Springfield, 7.62×39, .454 Casull, .45 Colt, .357 Magnum, .38 Special, .45 ACP, 9×19mm Parabellum, .380 ACP, .22 Long Rifle

The original Soviet M43 bullets are boat-tail bullets with a copper-plated steel jacket, a large steel core, and some lead between the core and the jacket. The cartridge itself consisted of a Berdan-primed, highly tapered (usually steel) case which seats the bullet and contains the powder charge. The taper makes it very easy to feed and extract the round, since there is little contact with the chamber walls until the round is fully seated. This taper is what causes the AK-47 to have distinctively curved magazines (helping to distinguish AK-47s from AK-74s, which feed from a much straighter magazine). While the bullet design has gone through a few redesigns, the cartridge itself remains largely unchanged.

From left to right: 7.62×54mmR, 7.62×39mm and 7.62×25mm Tokarev.

M43

Although the new cartridge represented a great leap forward from previous designs, the initial bullet design was flawed. The complete solidity of the M43 projectile causes its only drawback—it is very stable, even while traversing tissue. It begins to yaw only after traversing nearly 26 cm (10 in) of tissue.[9] This greatly reduces the wounding effectiveness of the projectile against humans. These wounds were comparable to that of a small handgun round using non-expanding bullets. Unless the round struck something vital, the wound was usually non-fatal, small and quick to heal.

M67

In the 1960s Yugoslavia experimented with new bullet designs to produce a round with a superior wounding profile, speed, and accuracy to the M43. The M67 projectile is shorter and flatter-based than the M43. This is mainly due to the deletion of the mild steel insert. This has the side effect of shifting the center of gravity rearward in comparison to the M43. This allows the projectile to destabilize nearly 17 cm (6.7 in)[9] earlier in tissue. This causes a pair of large stretch cavities at a depth likely to cause effective wound trauma. When the temporary stretch cavity intersects with the skin at the exit area, a larger exit wound will result, which takes longer to heal. Additionally, when the stretch cavity intersects a stiff organ like the liver, it will cause damage to that organ.

The wounding potential of M67 is mostly limited to the small permanent wound channel the bullet itself makes.[9] The real damage of the M67 occurs when it yaws.[9] Meanwhile a fragmenting round (like the 5.56×45mm NATO) might cause massive tissue trauma and blood loss (and thus rapid incapacitation) on a lung or abdominal hit, the M67 has a greater chance of merely wounding the target.[citation needed] However, the 5.56×45mm will only reliably fragment in close ranges below 125 metres (410 feet).[citation needed]

Many contemporary Russian-made 7.62×39 cartridges, such as those sold under the brand names Wolf Ammunition and Golden Tiger, feature a modified M67 bullet with an airspace cast into the nose, or similar ballistic-enhancing tip design (e.g. 8m3), which improves fragmentation and/or tumbling tendencies.

Chinese steel core

Chinese military-issue ammunition in this caliber is M43 style with a mild steel core and a thin jacket of copper or brass. Chinese ammunition (as well as all other M43 ammunition) is currently banned from importation in the US. U.S. federal law classifies the round as an armor-piercing handgun round. This classification is based on materials and bullet design rather than on empirical ability to penetrate armor.[10]

Cartridge dimensions

The 7.62×39mm has 2.31 ml (35.6 grains H2O) cartridge case capacity.

7.62×39mm maximum C.I.P. cartridge dimensions. All sizes in millimeters (mm).[11]

Americans would define the shoulder angle at alpha/2 ≈ 16.4 degrees. The common rifling twist rate for this cartridge is 240 mm (1 in 9.45 in), 4 grooves, Ø lands = 7.62 millimetres (0.300 in), Ø grooves = 7.92 millimetres (0.312 in), land width = 3.81 millimetres (0.150 in) and the primer type is small rifle. According to an American source some barrels can however have a non C.I.P. conform grooves diameter of 7.82 millimetres (0.308 in).[12]

According to the official C.I.P. (Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives) guidelines, the 7.62×39mm case can handle up to 355 MPa (51,488 psi) 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.

Hunting and sport use

Since approximately 1990, the 7.62×39mm cartridge has seen some use in hunting arms in the US for hunting game up to the size of whitetail deer, as it is approximately as powerful as the .30-30 Winchester round, and has a similar ballistic profile.[13] Large numbers of inexpensive imported semiautomatic rifles, such as the SKS and AK-47 clones and variants, are available in this caliber.

In addition, several AR15 manufacturers, such as Colt, Olympic Arms, Del-Ton Inc and ModelOne Sales, are producing 16" carbines and 20" to 24" rifle length firearms that can often get very good accuracy to about 1" groups at 100 yards.

Ruger produces the Mini-30 as a 7.62×39mm version of their popular Mini-14 rifle. They also once had their M77 Mark II available in this caliber.

Remington Arms introduced its Compact Model 799 Mini Mauser bolt action rifle chambered in 7.62×39mm in 2006, describing the Mauser action as "sought after by today’s hunters and shooters."[14] The Mauser action is a copy of the Gewehr 98 model rifle's action.

CZ-USA Sells the "micro length Mauser style" bolt action chambered in 7.62×39mm.[15]

Savage Arms has introduced (around 2010–2011) their own bolt action rifle in 7.62×39mm caliber - Model: 10 FCM Scout.[16]

The low cost and high availability of military surplus ammunition makes this cartridge attractive for many civilian shooters, although for hunting large game many people prefer the 154 gr soft point, which is usually labeled under the Wolf brand. A 126 grain Soft point is labeled under the MFS Brand and features a Zn (zinc) plated steel case, instead of the usual lacquer or polymer coated steel.

See also

References

  1. ^ "Wolf Rifle Ammo". Archived from the original on 5 September 2008. Retrieved 2008-09-05. {{cite web}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  2. ^ [1] clear.net.nz, Rifles. Retrieved on March 30, 2011
  3. ^ "Sellier & Bellot". Retrieved 2029. {{cite web}}: Check date values in: |accessdate= (help)
  4. ^ "Origin of AK Assault rifle and 7.62×39mm cartridge". Archived from the original on 27 September 2007. Retrieved 2007-09-25. {{cite web}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  5. ^ Bellamy RF, Zajtchuk R. The physics and biophysics of wound ballistics. In: Zajtchuk R, ed. Textbook of Military Medicine, Part I: Warfare, Weaponry, and the Casualty, Vol. 5, Conventional Warfare: Ballistic, Blast, and Burn Injuries. Washington, DC: Office of the Surgeon General, Department of the Army, United States of America (1990) pp. 146-155
  6. ^ U.S. Military Small Arms Ammunition Failures and Solutions, GK Roberts, NDIA Dallas, TX, 21 May 2008 http://www.dtic.mil/ndia/2008Intl/Roberts.pdf
  7. ^ Wounding Effects of the AK-47 Rifle Used by Patrick Purdy in the Stockton, California, Schoolyard Shooting of January 17, 1989, Fackler, Martin L. M.D.; Malinowski, John A. B.S.; Hoxie, Stephen W. B.S.; Jason, Alexander B.A., American Journal of Forensic Medicine and Pathology, September 1990
  8. ^ Bellamy RF, Zajtchuk R. The physics and biophysics of wound ballistics. In: Zajtchuk R, ed. Textbook of Military Medicine, Part I: Warfare, Weaponry, and the Casualty, Vol. 5, Conventional Warfare: Ballistic, Blast, and Burn Injuries. Washington, DC: Office of the Surgeon General, Department of the Army, United States of America (1990) Fig 4-38 p. 148
  9. ^ a b c d Military rifle bullet wound patterns - by Martin L. Fackler. From: http://www.uthr.org/SpecialReports/Military_rifle_bullet_wound_patterns.htm. Retrieved on November 9, 2011
  10. ^ "US Code: Title 18, Part 1, Chapter 44, § 921". Archived from the original on 20 October 2007. Retrieved 2007-09-25. {{cite web}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  11. ^ C.I.P. decisions, texts and tables free current C.I.P. CD-ROM version download (ZIP and RAR format)
  12. ^ The 7.62X39 at Guns & Ammmo.com
  13. ^ Warner, Ken (1989). Gun Digest 1990: 44th Edition. DBI Books. p. 147. ISBN 978-0-87349-038-2. Trajectories are identical according to Remington {{cite book}}: |access-date= requires |url= (help); More than one of |pages= and |page= specified (help)
  14. ^ "Compact Model 799™ Mini Mauser"
  15. ^ "CZ 527 Carbine"
  16. ^ "Savage 10 FCM Scout"
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