This is the Russian infantry weapon that has the US military so worried
Soviet military weapons have an odd tendency to stay both dangerous and relevant decades after they're issued. They might lack the creature comforts and modularity of modern firearm designs, but whether a bullet finds its mark from a World War I Mosin Nagant rifle, or a next generation Russian bullpup SVD sniper rifle, the result is the same.
The largest example of this, is the infamous AKM/AK-47. Every tin-pot dictatorship or ex-Soviet satellite nation has churned out terrifying numbers of these reliable automatic rifles. While the AKM is a deadly adversary at close and medium range, it is handily outclassed (both in accuracy, and effective range) by modern Western-made military rifles like the M4A3 and M16A4.
That said, there is one Soviet firearm that continues to confound and frustrate American military forces in the Middle East: the PKM.
The PKM or Modernizirovanniy Pulemyot Kalashnikova (PK Machinegun Modernized) is a belt-fed, open-bolt, long-stroke light machine gun chambered in the hard-hitting 7.62x54R cartridge — the same round used by Russian infantry in World War I, Vietcong snipers in Indochina, and modern Russian Federation snipers wielding the infamous Dragunov.
The internal workings of the PKM aren't dissimilar to those of the AK, and because of this, the PKM is remarkably reliable and resilient to negligent treatment. This robust construction combined with its powerful cartridge, make for an extraordinarily dangerous weapon against Western militaries — especially since the PKM has an effective range of 1,000-1,500 meters, putting it on par or surpassing most DMR rifles, and light machine guns in service.
Personally, after firing less than 100 rounds through a stateside PKM at an ordnance-testing facility in Nevada, I was able to successfully engage human-sized steel targets with iron sights at 600 yards with frightening regularity. This was with 60-year-old ammunition out of a PKM built in the 1970s with more than a half-million rounds fired through it.
The threat posed by this LMG to American and NATO forces is not lost on military thinkers or modern weapon-makers. In fact, the PKM is the impetus behind the latest evolution of the medium machine gun – the lightweight, medium machine gun, or LWMMG.
Historically, machine guns are grouped into three categories: light, medium and heavy (and occasionally general purpose). The last two, medium and heavy, are crew-served weapons, normally fired from either a tripod or vehicle mount. These are generally not considered man-portable, but are designed to provide constant fire on an area.
The light machine gun, or LMG generally fires a smaller caliber round than the medium or heavy machine gun, and is designed to be used and transported by a single soldier. These weapons are fired from a bipod, but are light enough to be quickly repositioned in the field.
The 5.56mm caliber M249 Squad Automatic Weapon (SAW) is a prime example of a light machine gun, while the .50 BMG M2 is a perfect example of a heavy machine gun. The M2 is tremendously more effective at all ranges than the M249, but its tremendous weight and size make it a poor choice for urban environments. The M240B almost splits the difference, but its 7.62 cartridge is still out-ranged by the Soviet PKM.
Thus the idea behind the LWMMG, is to combine the lightweight, portable nature of the the LMG with the extended range, and increased ballistic effectiveness of the MMG.
The engineers at General Dynamics are attempting this by incorporating a new "Short Recoil Impulse Averaging" method of operation coupled with a new modified .338 cartridge. At first glance, this seems like the scribblings of someone with no practical experience behind any of these weapon systems. On paper, a man-portable machine gun with the effective range of a .50 BMG, that weighed at little as the M240B with no more recoil than the 240, seems impossible.
If the footage of the new LWMMG released by General Dynamics is any indication, the new machine gun is more than just a concept. What remains to be seen, is whether or not the Pentagon puts enough importance on infantry combat and their equipment, to justify spending millions on upgrading it.
If nothing else, the likelihood of the General Dynamics LWMMG finding its way into the hands of US Special Forces is all but guaranteed. And while the increased effective range of the new cartridge is very impressive, the .338 round lacks the ballistic effectiveness of the .50 BMG. After all, it isn't intended to double as an anti-material round, nor does it have the anti-vehicle lineage of the .50 BMG cartridge.
That said, the .338 is designed with an ideal ballistic coefficient in mind — meaning the projectile itself sails through the air with minimal resistance. In effect, this means the rounds travel closer to where the soldier aims them.
In the traditional role of an MMG or HMG, this is sometimes seen as detrimental, as the weapon is supposed to be used to provide a field of fire to an area. If the rounds are too precise, the area might be under less wide-spread fire, and potentially leave some enemy combatants unsuppressed.
However, in this case, precision is key. Since the impetus behind the design is to counter insurgent PKM/PKP light machine guns. Conceptually, this should allow our soldiers to out-range insurgent elements, as well as provide more accurate counter-fire.
As for results, we'll have to wait and see if the idea gains more traction - and if it does, wait a few months or years for an official reports of its combat effectiveness to surface.