automatic

light machine gun

a pistol that will keep firing until the ammunition is gone or the trigger is released

operating with minimal human intervention; independent of external control; "automatic transmission"; "a budget deficit that caused automatic spending cuts"

resembling the unthinking functioning of a machine; "an automatic `thank you'"; "machinelike efficiency"

without volition or conscious control; "the automatic shrinking of the pupils of the eye in strong light"; "a reflex knee jerk"; "sneezing is reflexive"