A weapon that is ready to fire starts with the hammer back. Edge of trigger fits in groove cut into bottom of hammer to keep the hammer back against the tension of the spring. and engaged with trigger.
Pulling trigger causes trigger end to rotate out of groove releasing hammer.
Hammer drops on firing pin. Weapon fires.
Bolt carrier group pushes the hammer back into place.
If trigger is kept to rear, the disconnect engages the hammer to keep the weapon from firing continuously. When trigger is released, the disconnect rotates out of the way to allow the trigger to reengage with the hammer.
WHEN YOU’RE DONE HERE, GIVE THESE OTHER GUN SITES A SHOT: