5.8×42mm

5.8×42mm
5.8x42 mm.jpg DBP87 round
Type	Rifle
Place of origin	People's Republic of China
Service history
Used by	People's Liberation Army
Production history
Designer	People's Liberation Army
Designed	1979–1987
Produced	1987–Present
Variants	5.8×42mm DBP-87 5.8×42mm DBP-95 5.8×42mm DBP-88 heavy round 5.8×42mm DBP10
Specifications
Parent cartridge	None
Case type	Rimless, bottleneck
Bullet diameter	6.00 mm (0.236 in)
Neck diameter	6.65 mm (0.262 in)
Shoulder diameter	9.35 mm (0.368 in)
Base diameter	10.40 mm (0.409 in)
Rim diameter	10.42 mm (0.410 in)
Rim thickness	1.42 mm (0.056 in)
Case length	42.2 mm (1.66 in)
Overall length	58 mm (2.3 in)
Case capacity	2.11 cm3 (32.6 gr H2O)
Rifling twist	240 mm or 210 mm (1 in 9.45 or 1 in 8.27)
Ballistic performance Bullet weight/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

The 5.8×42mm / DBP87 ("Dàn (弹) Bùqiāng (步枪) Pŭtòng (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 5.45×39mm Soviet 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 are gradually succeeded by the DBP10 variant.

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 cartridge 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.

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.

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.

5.8×42mm cartridge variants

The DBP87/95 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. 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. Steel is less flexible than brass and therefore does not fill the chamber cavity as well when fired, decreasing the performance. A cleaner-burning propellant and a non-corrosive primer is used for the DBP-87.

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. 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). It is reported to have very good accuracy at 600 metres (656 yd).

The newest DBP10 cartridge variant has a hardened steel-cored 4.6 grams (71 gr) bullet and 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. The bullet has a ballistic coefficient (G7 BC) of approximately 0.193. It will replace all previous DBP87/95 and DBP88 5.8×42mm rounds. 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. DBP10 has an operating pressure of 255 to 289.4 MPa (36,980 to 41,970 psi). The DBP10 cartridge weighs 12.9 grams (199 gr). 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.

A new match round has been designed for QBU-88 designated marksman rifle to improve the rifle's complained accuracy, though no official information has been given.^{[citation needed]}

Use

• Chinese Type 87 assault rifle
• Chinese Type 95 / QBZ-95 assault rifle
• Chinese Type 95B / QBZ-95B carbine
• Chinese Type 95 LSW / Type 95 SAW / QBB-95 light support weapon / squad automatic weapon
• Chinese Type 88 / QBU-88 sniper rifle
• Chinese Type 03 / QBZ-03 assault rifle
• Chinese Type 88 / QJY-88 light machine gun
• Chinese Carbine portion ZH-05

See also

• 5 mm caliber
• 5.6×52mmR
• 6 mm SAW
• .243 Winchester
• 6.5×54mm Mannlicher–Schönauer
• 6mm BR
• List of rifle cartridges
• Table of handgun and rifle cartridges

External links

• Photo of 5.8 × 42mm ammunition
• QBZ-95 assault rifle
• QBZ-95 5.8mm Automatic Weapons
• PLA Moves Its Assault Rifle To Next Level by David M. Fortier
• Speculations On Load Choice, Development by David M. Fortier