.338 Norma Magnum MG


#1

An interesting new development from GD: a lightweight belt-fed MMG chambered in .338 Norma Magnum (not Lapua). I’ve been looking at it at the NDIA meeting in Seattle. The ammo is loaded with 300 grain MatchKings at the moment.


#2

Tony,

Did you manage to “find” any of the belt links? :-)

gravelbelly


#3

I took a couple of pics of the ammo belt but was being watched verrry, verrry carefully… ;-)


#4

The 300 grains Sierra MatchKing is the original loading for this ex wildcat and now proprietary number.

The .308" version, the 300 Norma magnum,was also developed around the 250 grains Sierra Match King bullet


#5

Story and pictures here: thefirearmblog.com/blog/2012 … gun-lwmmg/ along with some comments.


#6

From viewing the Pictures (on Gunblog) it seems that for the gun to feed properly, it must have a Cartridge delinker ( similar to Cannon) or be a “Pull out” operation, rather than a “Push through” Operation for feeding the cartridge cases from the Belt…as the .338NM is a BELTED Case…Of course, if the Belt on the cartridge has been removed, then a normal M13 Link design will work (or a German DM1)…I can’t see from the photos whether the case is Belted or not…

If it is not belted, then it is basically an up-calibred 8x63 Bofors (Swedish M32) Cartridge ( 8mm to 8,6mm).
Can anyone enlighten us as to the Feed mechanism? Tony E?

Admittedly, an intermediate ( 7,62 to 50cal/12,7mm) calibre might be suitable for long range “denial of passage” use, and even for somewhat more accurate fire, but is not the doctrine of MG use that of “Hard rain” over a comparitively large area, to deny the enemy the use of ground ( as espoused by the British in WW I with use of massed Vickers Guns, and by the Germans in WW II, with the cone of fire of the High ROF MG42? and the Russian/Soviet use of intersecting Fields of Fire with Maxim M1910s?

Now for the cost of the ammo…if the cost of the 8,6NM even approaches that of the .50/12,7 cartridge, the .50 will win out, on sheer practicality and effectiveness. Of course, if less than a .50 cal, then there may be some merit in the use of the 8,6NM… but why, when the 7,62 Nato does basically the same job out to 800 metres in the MG mode, and the .50 carries from there to 2000 plus metres…even the old .30M2 could with adjustments, be used in MGs up to 3000 metres “interdiction” Fire. ( the 173 grain M1 cartridge could go to 4,500 metres ( Gun at max. elevation), and the Vickers in .303 could do almost as good with Mark 8 boattail. It’s like Medieval Arrows fired at Maximum elevation…when they arrive, they still kill.

Now as to facility of use in the field…a .338/8,6mm MMG would need the same crew numbers as a .50 cal or even a 7,62 Cal Belt fed, and similar amounts of ammo to keep it fed, otherwise what’s the point?. Given this factor, and the the .338, whilst it is a good “sniper” cartridge, may be a waste of time and much money to develop and use as a “general area Weapon” (MGs to function tactically, must be an "area " weapon. It is not much use if ten bullets all hit the one man, when it only takes one bullet to incapacitate (or Kill) him…) Even the uncertainty of where a hail/burst of bullets will hit, is part of the psychological effect of MG fire…the “Hard Rain” principle.

I think, at this point, unless more details come out, that someone at GD though, the .,338LapM is an Accurate Cartridge, the old 308/.358NM ( a "normal length Cartridge) could be just as accurate in a .338 wildcat loading…the original .308 NM was developed in the USA as one of the original “short Magnum” cartridges able to feed without much receiver work, through a Normal M98 receiver ( of at least .30/06 Cartridsge capacity.).

This GD person then said, it would make an excellent, accurate MMG cartridge ( due to its inherent “sniper/hunting” characteristics), and this is where things start to go “pear-shape” ( British for “Snafu”).
Both from a Ballistics/MG doctrine side, and from a Logistics side. Effectively a totally New cartridge, in a new Gun design, for a totally useless (Tactical) aim, already well covered by existing MGs with a proven Tactical Record( in the case of the .50 cal, 90 years.).

I would like to see more on this “338NM” cartridge, and what its “figure of merit” (accuracy) Index is, and other features relating to its long range use ( remaining energy at target, time of flight, etc.).

Otherwise, we could just as well go back to a .30M1 Loading in an upgraded belt-fed MG of either MAG58 style, or even 1919 Browning style ( Both guns are Browning design origins – the MAG58 utilises the BAR 1918 Bolt mechanism.)

Ie, everything old is new again…or so the song goes.

Regards,
Doc AV


#7

Doc,
the 338 Norma magnum is a shortened 338 lapua magnum so it has no belt.

The shorter case lenght allow the use of the long Sierra MK bullet with the same OAL of the 338 Lapua magnum


#8

We are talking about a cartridge without showing it?

en.wikipedia.org/wiki/.338_Norma_Magnum


#9

Here’s my 338 Norma magnum sample( right) . On the left his brother 300 Norma magnum

viewtopic.php?f=8&t=8165&hilit=338+norma+magnum


#10

Here’s a pic comparing the 338LM and 338NM, posted on my forum:


#11

That clears up the problem…the original “Norma Magnum” cases were “belted”…that’s why I assumed (wrongly) that a .338 NM was a belted case as well ( derived from the old .358 or .308 NM)

SO in reality, the “.338NM” should not be called “NM” if derivation is indicated…
just a question of Parentage.

But that question is now moot…obviously, with a beltless ( traditional )case,the Link is a “push through” link; and that answers my intial question about feed mechanisms.
but my other considerations regarding Tactical use-ful(less)ness still remain.

Doc AV


#12

GD took the gun down to the range session at the end of NDIA, so (after a long wait in the queue) I was able to fire it. That is one impressive gun. I was instantly aware, from anywhere on the range, when it was firing. That deep, measured hammering sounds very different from all the 7.62mms and 5.56mms (which to my ears sound very similar). I couldn’t really judge recoil because it was on a tripod, but it stayed on-target between bursts. GD were obviously so confident about the gun that they gave literally scores of tyros like me the chance to shoot it, in a steady stream (they were working hard to belt up the ammo - Black Hills manufacture, loaded with 300 grain Sierra MatchKing).

Some notes from the GD presentation:

  • ballistic drop similar to .50 ball at 1500m
  • defeats Level III body armour 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.

I can imagine that troops facing long-range attacks in Afghanistan would be queueing up to carry this one into battle, despite the ammo weight. It provides what the US Army keeps stressing it needs: “overmatch”. Unlike the M240, which can only match the performance of the PKM (with a lot more weight), this one will make PKM gunners afraid.


#13

[quote=“gravelbelly”]Tony,

Did you manage to “find” any of the belt links? :-)
[/quote]

Thanks to the kindness of the GD folk, I did liberate one - it’s just a scaled-up M13 7.62mm link. Here’s a comparison pic, plus a strip of belted ammo: