The .338 Norma Magnum was originally developed as a long-range sport shooting wildcat cartridge by the American sport shooter Jimmie Sloan with the help of Dave Kiff, owner of Pacific Tool and Gauge, who made the reamers and headspace gauges. It was designed as a way to optimize shooting the 19.44 g (300 gr) 8.59 mm (.338 in) caliber Sierra HPBT MatchKing projectile from actions and magazines that lack the length to handle cartridges exceeding 91.44 mm (3.60 in) in overall length. Later the design was purchased by the Swedish ammunition manufacturer Norma. The .338 Norma Magnum cartridge was C.I.P. certified on 26 May 2010 and thus became an officially registered and sanctioned rimmed rifle cartridge. (Wikipedia)

    

  

From the press release by General Dynamics…
General Dynamics Armament and Technical Products, a business unit of General Dynamics (NYSE: GD), today unveiled a next-generation Lightweight Medium Machine Gun (LWMMG) at the Joint Armaments Conference in Seattle, Wash.

Identifying an unmet warfighter need, General Dynamics Armament and Technical Products conducted its own research and development program to develop the LWMMG in just over one year. The weapon is designed for low-cost production and for maximum effectiveness at the small unit level, where weight and lethality are decisive factors.

“The LWMMG is an affordable weapon that closes a current operational gap, providing .50 caliber-like firepower in range and effect at the same weight and size of currently fielded 7.62mm machine guns,” said Steve Elgin, vice president and general manager of armament systems for General Dynamics Armament and Technical Products. “Weighing in at 24 pounds and featuring a fully collapsible stock, the LWMMG offers superior mobility and portability in both mounted and dismounted operations.”

General Dynamics’ LWMMG also offers a distinct advantage in both extended and close-in fighting by using the highly efficient .338 Norma Magnum cartridge for increased accuracy and lethality out to 1,700 meters, a distance currently gapped in the operational capabilities of warfighters.

“By employing the larger .338 NM round, the LWMMG delivers twice the range and dramatically increases lethality above the 7.62 round,” said Elgin. “In addition, the LWMMG goes beyond providing suppressive fire and gives warfighters the ability to attack point targets at significantly extended ranges.”

The LWMMG has a firing rate of 500 rounds per minute, a maximum range of 5,642 meters, and is equipped with quick-change barrel technology. In addition to use by dismounted infantry and on ground vehicles, the weapon can be used as the armament system aboard helicopters and littoral craft, providing greater range and effectiveness for those platforms.

“The LWMMG is a well-designed machine gun ideally suited to provide long-range lethality to U.S. and allied forces,” Elgin said.

Some notes from the GD presentation:
• ballistic drop similar to .50 ball at 1500m
• defeats Level III body armor at 1000m
• delivers 4x the energy of 7.62mm at 1000m
• can maintain 10 minutes of continuous suppressive fire (50-100 rpm) without a barrel change
• very quick-change barrel (the carrying handle is on the barrel)
• quickly strips down into a few parts
• will fit on any M240 mounting (doesn’t need a soft mount – the mechanism has its own, built in)
• the gun mechanism is called Short Recoil Impulse Averaging: it uses gas operation, but the barrel group recoils in the receiver and fires as it is moving forwards, giving a very smooth recoil push rather than a series of sharp kicks
• forward-stripping link specially designed: normal load 50-round soft pouch
• weight of gun plus one minute’s worth of ammo (500 rounds) = 105 lbs, compared with similar load for M240 (800 rounds) = 100 lbs.
• GD working on polymer-cased ammo to reduce the weight.