Back and to the right?

[Royell Storing]

  When considering head movement relative to a shot striking the head, You also need to consider another shot also striking at the same general time. Also, remember that Jackie has ahold of JFK's wrist/hand and is pulling Downward and possibly toward herself in order to see what JFK is clutching at in his throat area. Also, for all we know, JFK is coughing or choking at the same time all of this is happening. That shot or shots is Not striking the Rock Of Gibraltar. There is movement/motion involved also.

[Gerry Down]

Also, for all we know JFK is coughing or choking at the same time all of this is happening. That shot or shots is Not striking the Rock Of Gibraltar. There is movement/motion Involved also.

That's a new one on me! JFK is just coughing in the Zapruder film 

And what was the head shot, a migrane? 

[Gary Craig]

  When considering head movement relative to a shot striking the head, You also need to consider another shot also striking at the same general time. Also, remember that Jackie has ahold of JFK's wrist/hand and is pulling Downward and possibly toward herself in order to see what JFK is clutching at in his throat area. Also, for all we know, JFK is coughing or choking at the same time all of this is happening. That shot or shots is Not striking the Rock Of Gibraltar. There is movement/motion involved also.

The car and JFK are moving forward when the bullet(s) strike his head and he's being held erect by the back brace /wrap.

The bullet doesn't need to throw his head back to create the effect just stop his head's momentum while his body and the limo continue forward. IMO

[Royell Storing]

That's a new one on me! JFK is just coughing in the Zapruder film 

And what was the head shot, a migrane? 

   Well, how often do You clutch at your throat when Not choking or coughing? Also, JFK just suffered being struck in the throat with a bullet. Please apply some Logic coupled with the Images you have seen.

[Royell Storing]

The car and JFK are moving forward when the bullet(s) strike his head and he's being held erect by the back brace /wrap.

The bullet doesn't need to throw his head back to create the effect just stop his head's momentum while his body and the limo continue forward. IMO

   Based on the Massive EXPLOSION we see on the Zapruder Film, there is going to be substantial head movement vs "just STOP his head's momentum". What you are contending occurs in "Road Runner" Cartoons.

[Gary Craig]

   Based on the Massive EXPLOSION we see on the Zapruder Film, there is going to be substantial head movement vs "just STOP his head's momentum". What you are contending occurs in "Road Runner" Cartoons.

  Evaluating the Zapruder Film by comparing it to the special effects of a Road Runner Cartoon?

That explains a lot. 

So you don't think the bullet(s) hitting JFK's skull from the right front stopped his forward momentum?

[Gerry Down]

The car and JFK are moving forward when the bullet(s) strike his head and he's being held erect by the back brace /wrap.

The bullet doesn't need to throw his head back to create the effect just stop his head's momentum while his body and the limo continue forward. IMO

Does that logic hold up though? Wasn't the limo almost stationary at the time of the head shot? Some witnesses thought the limo even stopped completely.