Timed Turret Firing


So about a week ago I asked for some help on how to get my turret objects to fire in any angle I rotate them in. After getting some assistance from some users I got the turrets to fire in the proper direction but now they fire a constant line of bullet objects, creating a beam of bullets.

Would anyone know what I'd need to do to make the turret fire only 1 bullet object every few seconds?
I'm assuming I need to set an alarm but for what specially and where in the turret object.

Any help is appreciated thank you