Grab and throw object immediately

Hello everyone, I would like that the player could grab an object and throw it using some force depending on the speed of the mouse and the angle/direction, I am using the script "DragRigidbody.js", it works well but there is an issue: The script makes sure to grab an object and can hold as long as the player would until it releases the right mouse button. What I would like is to only allow the player to catch an object and throw it immediately, for example grab it for 0.3 seconds, otherwise the object falls from his hands. Any help, please? Thanks