I ran into a panel in an 1840 farm house yesterday. The panel had been upgraded at some point to a Bryant panel. However many of the branch wires were short and they had terminated the ground on the panel cable clamps. My question is is that acceptable ?

That was a common method when grounding conductors started being built into the cables. Many circuits did not require grounding so it was backwrapped to keep it out of the way. It was typically a smaller gauge than the circuit conductors.

IMO they should have been extended into the bus.

Thank you for the reply I came to basically the same conclusion myself and that is what I reported to my client. If any one else has input I am interested to hear it.
Thank you