Metal Storm a Deadly Weapon System

“Metal Storm” – the very name provokes a mental image of metal raining from the skies.

Which, really, wasn’t far off the mark.

Metal Storm – developed by Metal Storm Ltd. (based in Brisbane, Australia) - had the ability to fire off a staggering amount of ammunition.  The prototype projectile machine gun system (one of several systems developed) was rated at 16,000 rounds of ammunition each second.

How could it do such a thing?  Well, it used the concept of a “superposed load” (also known as a “stacked charge”), which is multiple projectiles loaded nose to tail in a single gun barrel with propellant packed between them.  This was not a new concept – the idea dates back to the old matchlock and caplock firearms (actually further back than that, as the Roman Candle uses the same concept of multiple charges).  The desired aim was to have the ability to fire multiple shots from a single barrel without reloading.

  The “traditional” problem to the concept, however, is the issue of sequential charges firing together, instead of one after the other - which would often result in a burst barrel as well as injuries to the weapon wielder.

So, how did the Metal Storm system avoid the traditional problem?  With a combination of projectile design and an electronic firing system – the barrel and magazine were combined as a single unit, eliminating the need for a traditional firing mechanism.  And so, the system uses an electronic firing system - electronic impulses are sent directly to the bullets when the weapon’s trigger is pulled, which ignites them at an incredibly fast rate of 16,000 rounds a second.  Out of one barrel, that is astonishing enough – but the Metal Storm system combines multiple barrels (pictured above), and can fire bullets from several barrels at once.


Gun buffs may wonder about the issue of propellant gases – as I understand it, the projectiles were also redesigned to include some sort of “skirt” to prevent the hot gases from igniting the round(s) behind it in the barrel.

So, what kind of weapons are we looking at?


First up - the 9mm stacked projectile machine gun discussed above (named “Bertha”) had 36 barrels.  As a prototype, it demonstrated a firing rate of just over 1 million rounds per minute for a 180-round burst of 0.01 seconds. Firing within 0.1 seconds from up to 1600 barrels (at maximum configuration), the weapon system gun claimed a maximum rate of fire of 1.62 million rounds per minute - and creating a dense wall of 24,000 projectiles.  Indeed, a metal storm.

Next - the Multi-shot Accessory Under-barrel Launcher (MAUL) – an ultra-lightweight, electronically fired, semi-automatic 12-gauge shotgun that could be used either as an accessory weapon to a range of weapons (example - such as the M4 or M16 rifle) or as a stand-alone 5-shot weapon which could be fully loaded in less than 2 seconds, and fired repeatedly without cycling a conventional action.

The company had also developed (or at least patented ) a minigun with a belt of separate firing chambers using the electronic firing system.

Metal Storm also produced a semi-automatic 40mm grenade launcher with 3 grenades per magazine, for mounting under an assault rifle.  Though only 3 grenades per magazine, the system was stated to be able to fire grenades at a rate of a half-a-million rounds per minute. 

Back in 2007, the company announced that they had sold grenade barrels to the U. S. Navy’s weapon labs .  As well, they announced a memorandum of understanding with well-known American robotics firm iRobot (you know – those folks that make the Roomba vacuum cleaner) and showed off a droid armed with a quad-barrel Metal Storm 40mm grenade launcher, called FireStorm.

So, why aren’t any of the Metal Storm systems in wide-spread use?  Well, setting aside the minor detail that the company went into “voluntary administration” in 2012 (in Australia, a company in administration is operated by the administrator on behalf of the creditors as a going concern while options are sought short of liquidation)…

The fact is, one million rounds per minute of fire – in most cases – is just a very fast way of wasting ammunition. 

Oh, it sounds fantastic, sure – enough to have been featured in many magazines and a few television shows (such as History and Discovery Channel) after its debut, as well as being cited by the Guinness Book of Records as the world's fastest firearm - but in the end, there are only so many uses for a rate of fire that high – such as when trying to shoot down incoming missiles.  The U. S. Navy uses the MK 15 - Phalanx Close-In Weapons System (CIWS) system to do this, shooting at 4,500 rpm.  Unfortunately, the CWIS only has a 1,550 round magazine - so instead of putting up a "wall of metal", CWIS aims carefully (using its radar) and fires short bursts, and walks the rounds onto the incoming missile - just like a human machine gunner, conserving ammunition.

The Metal Storm system also faces a magazine limitation – so ask yourself:  does being able to fire one million rounds per minute make a whole lot of difference if one doesn’t have a one million round magazine?

And there were other complications to consider – the Metal Storm ammo was a bit more expensive than normal ammunition (remember I noted the rounds had a special design), so that would consume a larger chunk of anyone’s budget.  Once the magazine is expended, it’s also difficult to reload quickly - and the Metal Storm system need lots of barrels - for ammunition storage as well as for rate of fire – and those barrels are heavier than normal ones, not just because of the multiple projectiles, but also because of the need for induction electronics (the firing system) up much of the length of the barrel.

  So, using the example of an antimissile system, the multiple barrel system creates a substantial weight (and speed) penalty – because the heavier it is, the slower it can be moved - and in an anti-missile system, everything needs to be slewed round very fast.

So, in the end, several factors combined to cause the systems not to have been adopted into use in the U.S. Military.