A disruptor machinegun was a Romulan rapid-firing disruptor that required two people to be manned effectively. It fired large amounts of disruptor rounds and was used by the Romulan Ground Forces to combat enemy infantry. Also, it had a battery attached to it so it could draw its energy to fire. It was used to great effect against were-hawks to save an away team lost in the middle of the night. (RIS Bouteina: "Night of the Were-Hawks")
Hydrans also fielded a variation on this weapon, but built on the principles of a phaser instead. (RIS Bouteina: "Forlorn Hope")
Lyrans fielded disruptor machineguns when fighting large number of security guards, such as the assault on Starbase 148 by Akril's men, which required the Lyran Starfleet to deploy four disruptor machineguns on the premises. (Star Trek: The Stoneship Files: "Attack on the Laboratory")