A ton of grapes can produce about 60 cases, or 720 bottles of wine.
That number, however, is extremely approximate since the amount of juice from a ton of grapes varies. Grape bunches made up of small berries, there is a correspondingly higher ratio of skins, stalks, and stems. The amount of juice obtained also depends, of course, on how firmly the grapes are pressed.
The best estates barely press their grapes at all; much of the juice is simple natural “free run”.