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7.62×39mm

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7.62x39mm
Lateral view of a steel-cased 7.62x39mm FMJ cartridge.
TypeRifle
Place of origin Soviet Union
Service history
In service1945–present
Used bySoviet Union, Warsaw Pact, People's Republic of China, Cambodia, North Korea, Vietnam, Finland, Venezuela
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)
Rifling twist240 mm (1 in 9.45 in)
Primer typeBerdan or Boxer Small Rifle or Boxer Large Rifle
Maximum pressure355.00 MPa (51,488 psi)
FillingSSNF 50 powder
Filling weight24.7 gr
Ballistic performance
Bullet mass/type Velocity Energy
123 gr (8 g) Spitzer 710 m/s (2,300 ft/s) 2,010 J (1,480 ft⋅lbf)
154 gr (10 g) Spitzer SP 641.3 m/s (2,104 ft/s) 2,059 J (1,519 ft⋅lbf)
Source(s): Chuck Hawks[1]Wolf Ammo[2]

The Soviet 7.62x39mm rifle cartridge was designed during World War II and first used in the SKS carbine.

The cartridge was likely influenced by a variety of foreign developments, especially the pre-war German GeCo, 7.75x39mm experimental round,[3] and possibly by the late-war German 7.92x33mm Kurz ("Kurz" meaning "short" in German). 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. Its replacement, the 5.45x39mm cartridge, has less stopping power and armor penetration, but is highly lethal, has a flatter trajectory, and is more controllable in fully automatic fire due to the lower recoil. The change was in part a response to NATO switching from the 7.62x51mm NATO cartridge to 5.56x45mm NATO.[citation needed]

History

Oblique view of a steel-cased 7.62x39mm FMJ cartridge.
A 7.62x39mm M67 round next to a 7.62x25mm pistol cartridge
7.62x39 shown along side other cartridges. From left to right: 30-06, 7.62x39, .454 Casull, .45 Colt, .357 Magnum, .38 Special, .45 Auto, 9mm, .380, .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. [citation needed] The cartridge itself consists 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. While the bullet design itself has gone through a few redesigns, the cartridge itself remains largely unchanged.

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 stable even in tissue and begins to yaw only after traversing nearly 30cm (one foot) of tissue. This greatly reduces the wounding effectiveness of the projectile against humans. Dr. Martin Fackler noted that the wounds from the M43 round were comparable to that of a small handgun round using non-expanding bullets. Unless the round struck something vital, the wound was usually small and healed quickly.

M67

In the 1960s the Yugoslavians experimented with new bullet designs to produce a round with a superior wounding profile, speed, and accuracy to the M43. Dr. Fackler also evaluated the M67 in the same manner that he evaluated 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 17cm 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.

However, without fragmentation, the wounding potential of M67 is mostly limited to the small permanent wound channel the bullet itself makes. While a fragmenting round (like the 5.56x45mm 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 5.56x45 will only reliably fragment in close ranges below 125 meters.[citation needed]

Many contemporary Russian-made 7.62x39 cartridges, such as those sold under the Wolf, Golden Tiger, or Brown Bear label, feature a modified M67 bullet with an airspace cast into the nose or similar ballistic-enhancing tip design (e.g. 8m3) which improve 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. Contrary to common belief, the use of steel was a cost saving measure rather than one to increase penetration.[citation needed] Additionally, mild steel is not sufficiently hard to grant unusual armor penetrating capability.[citation needed] Despite this, Chinese ammunition (As well as all other M43 ammunition) is currently banned from importation in the US because there are 7.62x39mm caliber handguns and the ammunition is an armor-piercing handgun round under the U.S. federal legal definition of the word, which is based on materials and bullet design rather than on tested ability to penetrate armor.[4]

Ballistics

The standard AK-47 or AKM fires a 7.62x39mm round with a muzzle velocity of 710 metres per second (2,329 ft/s). Muzzle energy is 2,010 joules (1,467 ft·lbf). Cartridge case length is 38.6 millimetres (1.5 in), weight is 18.21 grams (281.0 grains). Projectile weight is normally 8 grams (123 gr). The AK-47 and AKM, with the 7.62x39mm cartridge, have a maximum effective range of around 400 meters.

Cartridge dimensions

The 7.62x39mm has 2.31 ml (35.6 grains H2O) cartridge case capacity.

7.62x39mm maximum C.I.P. cartridge dimensions. All sizes in millimeters (mm).[5]

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 = 7.92 mm, Ø grooves = 7.62 mm, land width = 3.81 mm and the primer type is berdan or small rifle or large rifle.

According to the official C.I.P. (Commission Internationale Permanente Pour L'Epreuve Des Armes A Feu Portative) guidelines the 7.62x39mm 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.

Other names for 7.62x39mm

On some occasions, this ammunition is referred to as 7.62 mm Soviet, 7.62 mm Warsaw Pact, or 7.62 mm ComBloc. It was also known in the United States as .30 Short Russian/ComBloc; the "Short" was to distinguish it from the older .30 Russian, which was the 7.62x54mmR. (Note that the "R" in 7.62x54mmR does not stand for "Russian", but "Rimmed".)

Hunting and Sport Use

Since approximately 1990, the 7.62x39mm 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 old .30-30 Winchester round, and has a similar ballistic profile.[6] Large numbers of inexpensive imported semiautomatic rifles, like the SKS and AK-47 clones and variants, are available in this caliber. The SKS is so inexpensive as to have begun displacing the .30-30 lever-action rifles as the new "poor man's deer rifle" by being less expensive than the .30-30 Marlins and Winchesters that long held that role.[citation needed] In addition, Ruger produces the Mini-30 as a 7.62x39mm version of their popular Mini-14 rifles. Inexpensive imported 7.62x39mm ammunition is also widely available, though some of it is the older non-expanding and steel core type that may be illegal to use for hunting in some US states. However, both imported Russian ammunition like Wolf brand and American civilian manufacturers produce both hollow-point and soft-point rounds, which are suitable and nearly universally legal for hunting except in areas where the use of rifles for hunting is completely prohibited, and most modern FMJ ammunition sold today features improved tumbling or fragmentation variants of the M67 bullet, such as the rebranded Ulyanovsk produced 7.62x39-8m2 and 8m3 "effect" typically sold in sealed metal cans.

7.62x39mm ammunition has typically been one of the least-expensive centerfire rifle ammunitions on the market. It cost just over 17 cents a round for quality imported ammo in early 2006[citation needed]. In 2005/2006, prices began to soar (almost doubling in the US) due to the United States placing a massive order to supply the fledgling Afghan and Iraqi armies.[7] Average price in early 2008 rose to 22 cents per round, bought in bulk packs of 500 to 1000. It is still cheaper than most handgun rounds and even some expensive target .22 rimfire ammunition. This cartridge has endeared itself to shooters in spite of its limited ballistics,[citation needed] because of the many inexpensive good semiautomatic rifles available for it, the availability of inexpensive ammunition, and because of its minimal recoil.[citation needed]

As of 2009 many retailers (online and otherwise) are either out of stock and on backorder or have ceased sale all together since a massive surge in sale since the last US presidential election. As one retailer stated "People come in and ask if we have any in stock, we say yes, and they buy every last bit of it."

See also

References

  1. ^ "The 7.62x39mm M43". Retrieved 2007-09-25.
  2. ^ "Wolf Rifle Ammo". Retrieved 2008-09-05.
  3. ^ "Origin of AK Assault rifle and 7.62x39mm cartridge". Retrieved 2007-09-25.
  4. ^ "US Code: Title 18, Part 1, Chapter 44, § 921". Retrieved 2007-09-25.
  5. ^ C.I.P. decisions, texts and tables free current C.I.P. CD-ROM version download (ZIP and RAR format)
  6. ^ "CZ Mod 527 (7.62x39mm)", theothersideofkim.com, retrieved 20 October 2007.
  7. ^ "US sets up £215m deal for Afghan arms - from Russia", telegraph.co.uk, retrieved 2 October 2006.