The History and Failure of the Metal Storm Firearm

The Fastest Fire Rate Machine Gun That Was Never Used

Silhouette of a US soldier at sunrise holding a Metal Storm firearm.

Lucas Jackson-Pool / Getty Images

The name “Metal Storm” provokes a mental image of metal raining from the skies. Metal Storm is, in fact, the name of a new version of the Gatling Gun but with no mechanical parts of the gun to slow it down.

Without mechanical parts, it can produce a hail of lead downrange at the rate of 16,000 rounds per second. The fastest Gatling Gun was capable of producing between 2,000 to 6,000 rounds per minute. Compared with some of the fastest machine guns (1,000 rounds per minute) in the U.S. arsenal of weapons, the Metal Storm is exponentially faster.

Metal Storm, developed by Metal Storm Ltd. (now DefendTex) in Brisbane, Australia, had the ability to fire off a staggering amount of ammunition. Metal Storm also has two modes. It can create a metal spear of sorts by placing several rounds in a straight line—even piercing armor. Also, it can create a metal wall of bullets capable of stopping an incoming missile similar to the shipboard weapons system known as the Phalanx CIWS—Close-In Weapon System. Still, the CIWS has a rate of fire of just 4,500 rounds per minute.

The Details Behind the Metal Storm's Rapid Fire Rate

Metal Storm uses 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 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. 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. 

With the 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 and can fire bullets from several barrels at once.

Metal Storm 1

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 1,600 barrels (at maximum configuration), the weapon system gun claimed a maximum rate of fire of 1.62 million rounds per minute, creating a dense wall of 24,000 projectiles—indeed, a metal storm.

Metal Storm 2

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 (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.

Metal Storm 3

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 4

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 and showed off a droid armed with a quad-barrel Metal Storm 40mm grenade launcher, called FireStorm.

Why the Powerful Machine Gun Didn't Work Out

The Metal Storm systems are not particularly in widespread use because in most cases, this many rounds per second can be a big waste of ammunition. Besides, the Australian company went into “voluntary administration” in 2012 similar to a restructuring bankruptcy in the United States.

It sounded fantastic 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 Metal Storm system also faces a magazine limitation: Does being able to fire 1 million rounds per minute make a whole lot of difference if one doesn’t have a 1-million-round magazine, or 1 million rounds handy at the moment?

In the end, several factors combined to cause the Metal Storm not to have been adopted into use in the U.S. Military. The extra cost of the ammunition, waste of ammunition during firing, massive amounts of ammunition, and limited magazine size all combined to make this an expensive dud for practical use.