I have seen two ND, one with a M700 and one with a M70, both occurred on the bench by someone who went to release the safety when their finger was slightly inside the trigger guard. When the thumb went forward to release the trigger, the motion caused the finger in the guard to also move and voila!, "it went off when I released the safety!" Not saying that explains the issue, but I bet some of these failures are more like ND than failures.
