4.6 x 30 mm
From Wikipedia, the free encyclopedia
The 4.6 x 30 mm cartridge is a type of ammunition used in the H&K MP7 PDW and by the H&K UCP pistol. It is designed to minimize weight and recoil while increasing penetration of body armor.
Contents |
[edit] Summary
It features a bottlenecked case and a pointed, steel-core, brass-jacketed bullet.
- Projectile weight: 24.7 grains (1.6 g)
- Muzzle velocity: 2,378 ft/s (725 m/s)
- Muzzle energy: 420 J.
- Effective range: 200 m
Test results provided by hkpro.com:
- Penetration of a ballistic gelatin block at 50 m (20 % gelatin block 300 mm long) - 280 mm (11 in)
- Energy transfer through body armor at 50 m (1.6 mm titanium + 20 layers of Kevlar) - 220 J
- Energy transfer through body armor at 100 m (1.6 mm titanium + 20 layers of Kevlar) - 115 J
The same tests were performed on the 5.7 x 28 mm round:
- Penetration of a ballistic gelatin block at 50 m (20 % gelatin block 300 mm long) - 230 mm
- Energy transfer through body armor at 50 m (1.6 mm titanium + 20 layers of Kevlar) - 140 J
- Energy transfer through body armor at 100 m (1.6 mm titanium + 20 layers of Kevlar) - 65 J
The round was designed as a competitor to the 5.7 x 28 mm round developed by Fabrique Nationale. In head-to-head comparison of the two rounds, 4.6 x 30 mm fired out of the MP7 is slower and offers slightly shorter range and reduced terminal ballistics than the 5.7 x 28 mm fired out of the P90. SS195LF, with a 28 grain projectile, fired out of the P90 can achieve muzzle velocities of approximately 2500 ft/s.
The 4.6 x 30mm cartridge and the 5.7 x 28 has been criticized for their supposedly low terminal effectiveness. This claim comes especially from those who discount the "energy dump" theory of wound ballistics such as Dr.Martin Fackler and Dr. Gary Roberts. Kinetic energy manifests itself in human tissue in temporary stretching of tissue, which most tissue except for liver and neural tissue is able to withstand with little ill effect. Dr. Fackler and Dr. Roberts claim that the combination of permanent wound cavity and frequently insufficient penetration (the FBI recommends a minimum of 12 inches of penetration in ballistic gelatin) make these PDW cartridges terrible terminal performers.
The latest version ("Ultimate Combat") uses a 2g steel projectile at the same velocity, giving it a moderate edge in penetration over the 5.7 x 28 mm cartridge. Terminal effectiveness is more comparable to the 5.7mm cartridge due to the increase in energy delivery.
Muzzle Energies Compared:
Original 4.6mm: 420 Joule, 310 ft/lbs (fired from MP7)
Standard 5.7mm: 513 Joule, 379 ft/lbs (fired from P90)
2g Steel 4.6mm: 525 Joule, 388 ft/lbs (fired from MP7)
