For many centuries gunpowder was the explosive propellant of choice in warfare, partly because there was little else to actually choose from.
However, inevitably modern technology has evolved, and so too did the gun and its ammunition. Careful experiments in the early-20th Century made way for anti-aircraft cannons that harnessed the intense power of electricity, and soon after the railgun was born.
A railgun consists of two conductive rails (also known as bars), electrical current, and a projectile, such as a rocket or missile. The two rails sandwich the conductive projectile, which is itself encased inside a shell to make for a complete electrical circuit. Apart from nearly overheating and melting due to the immense amount of friction inside the gun created every time it’s fired, a railgun is a truly groundbreaking step from its former ally: gunpowder.
Ammunition in a railgun is propelled with the help of magnetism. As the electrical current flows through one of the rails, it passes through the projectile and onto the opposite rail. One of the rails becomes positively charged and the other becomes negatively charged.
This rapidly heating mechanism naturally creates an electromagnetic field. This swirls around both rails holding the projectile, forming an overwhelming power.
As the two rails are carrying electrical current in opposite directions the projectile is eventually forced away from the ends of the rails and out of the barrel. The speed all depends on how much current is used and the length of both rails, but can be up to ten times faster than a weapon using gunpowder.
The materials for a railgun have to be highly heat resistant, and they are built to withstand extreme opposing forces made when the projectile is fired. It’s also worth considering that the cost of electricity used to power a single railgun is colossal but could be greatly offset as the cost of otherwise-lost bullets is reduced.