You hurl a thrown weapon from your hand, rather than using it to loose a projectile. A ranged basic attack with a heavy thrown weapon uses your Strength.
Any magic heavy thrown weapon automatically returns to its wielder's hand after a ranged attack with the weapon is resolved. Catching a returning thrown weapon is a free action. If the wielder does not wish to catch the weapon, it drops in the wielder's space. [PH:232][RC:282]