WASHINGTON • The US Navy is quietly pushing ahead with a radical new cannon that could one day transform how wars are fought.

Called the railgun, the weapon represents a paradigm shift in ballistic technology.

Instead of using gunpowder and explosive charges to shoot a shell from its barrel, it employs vast amounts of electromagnetic energy to fire a projectile along a set of copper-alloy rails.

Four small fins on its rear then help guide the round towards a moving object - such as an enemy ship, drone or incoming ballistic missile. It relies purely on the kinetic energy from its vast momentum to destroy the target.

Ultimately, scientists expect the railgun rounds to travel at speeds of up to Mach 7.5, which - at 9,100kmh - is more than seven times the speed of sound. The rounds are expected to be able to cover a distance of about 160km.

"The railgun is revolutionary in terms of how much it can accelerate the bullet," said Mr Tom Boucher, the railgun programme manager at the Office of Naval Research, at the Pentagon as he displayed six interconnected steel plates that all had been shredded by a single test round.

Currently, it requires about 25MW of energy to power a railgun. That kind of power, and the space needed to generate or store it, rules out many vessels from hosting it, but researchers are optimistic that the technology will grow more compact.

Mr Boucher said he is optimistic the gun will ultimately end up being operationally deployed, probably within a decade.

It is not just the navy that has its sights on the railgun. The US Army would one day like to put the electric blasters on its tanks, but is currently constrained by the gun's power requirements.

AGENCE FRANCE-PRESSE