Precise timing is required to fire at its labeled fire rate, practice lining up shots and timing the next shot to find out the ideal speed at which to press the fire button. A faster fire rate will require slightly faster timing.
Like the Kraken, there is a slight delay after firing where reloading will not function, and requires a double click or a pause then click for it to actually reload. This can be frustrating.
As this is a burst fire weapon, move the mouse down after firing shots.