A machine gun is defined as a weapon that can fire a number of shots with one continuous pull of the trigger. (politifact.com)
I think about it because the disability I have now, that I acquired with a one - second pull of a trigger, turned my life upside down. (talkpoverty.org)
An automatic firearm delivers a continuous stream of bullets as long as the trigger is held, while a semi-automatic weapon requires a new pull of the trigger for each bullet. (sun-sentinel.com)