Half turn in swing followed by front somersault with a 1½ twists
1 Front Somersault
Start this trick like a cutaway. When you let go of the bar, initiate the one and a half twists (known as a 'Rudy'). If you try to pull this twist off of the bar you will find that the bar will not swing back straight and your return bar will be impossible. As you exit the twist, the catcher will be there to take your arms.
You can find out more about this trick in following books: