The binary trigger and bump stocks work differently than forced-set triggers. Bump stocks, for example, are frames or components added onto the back of semi-automatic weapons that use the recoil ...

His gun had a binary trigger, which allows a semi-automatic firearm to fire two bullets at a time: one at the pull of the trigger and one at the release.

Gun control A new Minnesota law prohibits guns with "binary triggers" that allow for more rapid fire, causing a weapon to fire one round when the trigger is pulled and another when it is released.