HK MP7
The Heckler and Koch MP7 is a submachine gun, classified as a personal defense weapon (PDW). It went into production in 2001. Like the conceptually similar FN P90, it is very compact (340 mm) and light (1.3 kg unloaded), using mainly polymers in the construction.
The proliferation of high-quality body armor has begun to make guns that fire pistol ammunition (such as HK's earlier MP5 or the USP) ineffective. In response to this trend, HK designed the MP7 to be powerful enough to penetrate body armor, but small enough to be used in place of either a pistol or a submachine gun.
The MP7 essentially operates like a scaled down assault rifle, with the same action as HK's G36 assault rifle. The MP7 fires a specially-designed, armor-piercing 4.6×30 mm round that travels nearly as fast as the 5.56×45 mm NATO round used by many modern rifles. This ammunition is unique among submachine guns in that the bullet is made almost entirely of a hardened steel penetrator instead of softer brass or lead. That said, the MP7 is slated to give the firepower of an assault rifle and the concealability of a large pistol.
The weapon allows for a conventional 20 or 40 round box magazine fitting within the pistol grip and has a ambidextrous fire-select lever and rear cocking grip. It has an extendable stock and a folding front grip. It can be fired either one- or two-handed.
It fires at a maximum rate of 950 rpm (rounds per minute) using a open bolt gas system, similar to the company's G36. The ammunition is specific to the gun, designed for good penetration and low recoil. The 4.6×30 mm steel bullet weighs only 1.6 gram (unit) and has a velocity of 725 m/s with a muzzle energy of 420 joules. Despite the small caliber, the bullet has better penetration characteristics than the 5.7×28 mm round used in the P90 at the weapon's maximum range of around 200 metres.
