Does that model of JC , that Jerry just posted here, represent fairly accurately the position of JC at Z270 as proposed by Andrew?
If so , a bullet hitting JCs right hand/wrist and exiting the palm of the hand, would have had to go thru the hat if the bullet entered JCs left inner thigh.
The motions of JCs right shoulder suddenly rotating beginning at Z225 and the right hand clutching hat suddenly upward, beginning approx Z230 seem to me more likely due to involuntary reaction of JC to being hit by a bullet, as opposed to JC just merely trying to turn around after hearing a rifle shot fired.
If Jerry’s model which has both JCs legs parallel with the longitudinal axis of the limo is the actual orientation , then theoretically JC should have been able to twist his upper body around equally right or left.
However, imo, JC did NOT twist around to his left as much as he did to his right during those movements from Z225-z270.
This suggests that perhaps JC had both his legs rotated towards the right side door when he was in the Z224 position, and that this precluded him from twisting around to look over his left shoulder enough to see JFK.
JC therefore resorted to twisting around more to his right side and was able to see JFK just before JC began to fall backwards into Mrs C lap.
If Jerry is willing, perhaps an adjusted model with both of JCs legs turned towards the right side door and the right hand holding hat over the left leg will solve the hat problem.