Please, please listen to Sasparilla. The prosecutor is going to have pros at his/her disposal who will testify to nearly anything the state wants. Find someone who will take the stand. That's what this is going to take.
My own non-expert but reasonably informed opinion is that a direct shot to the head with a .223 at close range is likely to cause unmistakable permanent cavity damage that will be in excess of anything expected from a ricochet. My opinion and three bucks will buy you a cup of coffee.
Actually, this is how this started.
My attorney client wanted me to find an expert on guns and we started talking about the case. He wanted someone to evaluate the status of the rifle (working order, trigger mechanism, etc.) and as we talked I realized that wasn't at all where the case's fulcrum was.
The case hinged on whether the defendant's gun shot at the floor first, or at the victim.
If at the floor, then no murder.
Thus, my questions.
We haven't ruled out any experts. It's just that the target (excuse the pun) needs to be calibrated.
FYI, McDonald's coffee is only a buck, and its better than Starbucks.