The rifle, called the DroneDefender, uses a radio pulse to disable a targeted drone within 400 meters. The gun causes the drone to think it's out of range and enter emergency protocol, either causing it to land, hover or return to its point of origin.
Because the DroneDefender jams communications between the drone and the operator, it can also prevent any onboard self destruct mechanisms from going off.
Battelle Innovations, the company responsible for producing the rifle, says that it is "a lightweight easy-to-use non-kinetic solution to defend airspace against UAS without compromising safety or risking collateral damage." Because no bullets are being fired, there is little chance something or someone else will get hurt.
Here is some video of the weapon in operation
It is awesome to see humans tame machines with electromagnetism.