5.8×42mm

The 5.8×42mm / DBP87 ("Dàn (弹) Bùqiāng (步枪) Pŭtōng (普通), 1987"; literally "Standard Rifle Cartridge, 1987") is a military rimless bottlenecked intermediate cartridge developed in the People's Republic of China. There is limited information on this cartridge, although the People's Liberation Army says that it is superior to the 5.56×45mm NATO and Soviet 5.45×39mm cartridges. Another variant called the DBP88 "heavy round" was designed specifically for squad automatic weapons and designated marksman rifles. The 5.8×42mm "heavy round" cartridge has the same dimensions as the standard 5.8×42mm cartridge, but utilizes a longer streamlined bullet with a heavy steel core for increased performance at extended ranges and penetration. As of 2010 all 5.8×42mm cartridge variants have been succeeded by the DBP10 variant.

5.8×42mm
DBP87 round
TypeRifle
Place of originPeople's Republic of China
Service history
Used byPeople's Liberation Army
Production history
DesignerPeople's Liberation Army
Designed1979–1987
Produced1987–Present
Variants5.8×42mm DBP-87
5.8×42mm DBP-95
5.8×42mm DBP-88 heavy round
5.8×42mm DBP10
Specifications
Parent caseNone
Case typeRimless, bottleneck[1]
Bullet diameter6.00 mm (0.236 in)
Neck diameter6.65 mm (0.262 in)
Shoulder diameter9.35 mm (0.368 in)
Base diameter10.40 mm (0.409 in)
Rim diameter10.42 mm (0.410 in)
Rim thickness1.42 mm (0.056 in)
Case length42.2 mm (1.66 in)
Overall length58 mm (2.3 in)
Case capacity2.11 cm3 (32.6 gr H2O)
Rifling twist240 mm or 210 mm
(1 in 9.45 or 1 in 8.27)
Ballistic performance
Bullet mass/type Velocity Energy
4.15 g (64 gr) DBP87/95 FMJ 930 m/s (3,100 ft/s) 1,795 J (1,324 ft⋅lbf)
5 g (77 gr) DBP88 FMJ 870 m/s (2,900 ft/s) 1,892 J (1,395 ft⋅lbf)
4.6 g (71 gr) DBP10 FMJ 915 m/s (3,000 ft/s) 1,926 J (1,421 ft⋅lbf)
Test barrel length: 557mm (21.9 in)
Source(s): Anthony Williams[2][3]

History

China started development of the 5.8×42mm cartridge in 1979 and finalized the cartridge in 1987. The 5.8×42mm / DBP87 was designed to replace the Soviet 7.62×39mm and 5.45×39mm cartridges used by the People's Liberation Army (PLA). The Type 95 / QBZ-95 (Chinese: 轻武器,步枪,自动, 1995; Pinyin: Qīng wǔqì, Bùqiāng, Zìdòng, 1995; literally "Light weapon, Rifle, Automatic, 1995") 5.8 mm caliber assault rifle, firing the 5.8×42mm / DBP87 or the improved DBP95, is now the standard issue weapon in the PLA. The DBP87 service round was quickly supplemented in 1988 by the DBP88 round which was loaded with a heavier more aerodynamic projectile for improved extended range performance.

The 5.8×42mm is an example of an international tendency towards relatively small sized, light weight, high velocity military service cartridges. Cartridges like the American 5.56×45mm NATO, Soviet 5.45×39mm and 5.8×42mm allow a soldier to carry more ammunition for the same weight compared to their larger and heavier predecessor cartridges, have favourable maximum point-blank range or "battle zero" characteristics and produce relatively low bolt thrust and free recoil impulse, favouring light weight arms design and automatic fire accuracy.[2]

In June 2004, an improved version of the 5.8×42mm cartridge entered development as the matching ammunition for the revised assault rifle, Type 95-1. Both designs were finalized in 2010 and production began the same year. This new cartridge is known as DBP10.

To improve accuracy and barrel life the barrel was also redesigned. The number of rifling grooves was increased from 4 to 6. The diameter of the lands was slightly increased from 5.8 to 5.84 mm to 5.82 to 5.86 mm. The groove diameter was decreased from 6.01 to 6.07 mm to 5.98 to 6.02 mm. In addition, the twist rate in the revised 95-1 assault rifle was reduced from 240 mm to 210 mm. These changes reduced the rifling twist rate from 41.2 to 36 calibers.

The People's Liberation Army claims that the 5.8×42mm is superior to the 5.56×45mm NATO SS109 and the 5.45×39mm 7N6; stating it has better armor penetration of 10 mm at 300 meters, a flatter trajectory, and a higher retention of velocity and energy downrange.[2]

5.8×42mm cartridge variants

The DBP87 cartridge with 4.15 grams (64.0 gr) bullets has a muzzle velocity of 930 metres per second (3,051 ft/s) from a standard barrel (Type 95 / QBZ-95, 463 mm barrel length), and 940 to 960 metres per second (3,084 to 3,150 ft/s) from the Type 95 LSW (557 mm barrel length). The bullet has a ballistic coefficient (G7 BC) of approximately 0.156.[4] The steel core has a diameter of 4.1 millimetres (0.16 in). In order to save cost, several compromises were made. In particular, the cartridge case is made of steel, which is cheaper than brass. To reduce the chance of rust, the case is covered in a thin layer of protective paint in dark brown. To ensure high extraction reliability, the case has a thick rim and a large extractor groove. [5][6]

The DBP88 "heavy round" cartridge has a 5 grams (77 gr) bullet and a muzzle velocity of 870 metres per second (2,854 ft/s) from a standard barrel (Type 95 / QBZ-95, 463 mm barrel length), and 940 to 960 metres per second (3,084 to 3,150 ft/s) from the Type 95 LSW / Type 95 SAW / QBB-95 (557 mm barrel length), and 895 metres per second (2,936 ft/s) from the Type 88 / QBU-88 (620 mm barrel length). The bullet has a ballistic coefficient (G7 BC) of approximately 0.210.[4] It has an effective range of 800 metres (875 yd) and can penetrate 3 mm steel plates at a distance of 1,000 metres (1,094 yd).

The DBP95 cartridge was developed in 1995 for the QBZ-95. The DBP95 is an improved version of the DBP87 that uses a cleaner propellant and non corrosive primer. Its performance remains similar and the production costs are higher, but the negative effects on the weapon are reduced. It is basically the same round as the DBP87 other than these minor differences, and was used until 2010 when it was replaced by the DBP10. [7]

The DBP10 cartridge is the newest 5.8mm variant to date. It was developed in 2010 and has a hardened steel-cored 4.6 grams (71 gr) bullet, a muzzle velocity of 915 metres per second (3,002 ft/s) and is designed to match all currently serving 5.8×42mm chambered weapons. As such, it will consolidate and replace all previous DBP87/95 and DBP88 5.8×42mm rounds. The bullet has a ballistic coefficient (G7 BC) of approximately 0.193.[4] Major improvements include a non-corrosive primer, a copper-coated steel case with a copper alloy bullet jacket with a 3.8 millimetres (0.15 in) diameter hardened steel core for better penetration of (body) armor. It also uses a cleaner burning propellant so as not to leave residue inside the weapon after firing. However, although testing of the previous DBP87/95 5.8 mm rounds showed that they were less likely to cause serious wounds, the issue was not addressed with the new DBP10 round.[8][9] DBP10 has an operating pressure of 255 to 289.4 MPa (36,980 to 41,970 psi).[10] The DBP10 cartridge weighs 12.9 grams (199 gr).[4] Accuracy of fire at 300 m (328 yd) (R50) is stated as 75 mm (3.0 in), at 600 m (656 yd) (R50) is stated as 140 mm (5.5 in) and at 800 m (875 yd) (R50) is stated as 230 mm (9.1 in). R50 at a specific range means the closest 50 percent of the shot group will all be within a circle of the mentioned diameter at that range. The circular error probable method employed by the Chinese and other (European) militaries cannot be converted and is not comparable to the common US methods (groupsize of 5 or 10 successive shots fired at 100 yards) for determining accuracy.

Use

See also

References

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