ARDE (DRDO) has successfully developed a 10MJ (mega joules) EM Railgun indigenously. Further development of up to 100MJ will be carried out at a dedicated infrastructure facility ‘CEMaLT’ which is currently under construction as per a report published in DRDO Newsletter publication.

Railguns have the experimentally proven capability to accelerate masses of several kilograms to velocities in excess of 2 km/s. For military payloads railguns are attractive accelerators, as they have the capability to reach velocities in excess of what explosively driven guns can achieve. In the military domain masses from 0.1 kg up to several kilograms need to be accelerated to velocities in between 2 km/s to 3 km/s.

High-speed Photograph for velocity measurement realisation

Projectile accelerates in a conventional gun barrel due to propellant burning in the gun chamber. But there is a limit to how much propellant can be filled in the chamber of a gun. A gun requires a larger chamber volume to accommodate a higher amount of propellant resulting reduction in pressure. The maximum velocity with which the gases can accelerate the projectiles is a function of the speed of sound in the gas.

The gun propulsion techniques in the conventional weapon is summarised in Figure below.

Latest technology in the name of EM propulsion is being explored in which EM energy due to Lorentz force is used to propel a projectile. This type of propulsion system has no such theoretical limit of velocity of the medium unlike the gases in chemical energy-based propulsion; as electromagnetic phenomena travels with the speed of light.

Using programmable pulsed power technology, a railgun based on 10 MJ capacitor bank has been successfully designed, developed, and installed at ARDE, Pune. Hypervelocity propulsion of >2000 m/s has been achieved by using this facility. Using the 10 MJ EM railgun, a series of dynamic firing trials from a fixed firing stand was conducted for experimental evaluation and system performance. These experiments has helped to characterize EM railgun for different bore sizes up from 12 mm to 45 mm for projectiles of 80 gm, 120 gm, 250 gm, and 500 gm.

Based on the know-how gained after the successful completion of Technology Demonstration (TD) project, the configuration and design methodology can be extended to achieve higher speed, range, and
lethality in futuristic rail gun.