Glowing white blob/projectile firstly strikes cuff area of JFK's jacket and proceeds to strike JFK in the jawline, velocity of projectile forces JFK's centered head from facing the front to his left. Physics - Newton's second law of motion - in short, an object hit by a projectile will be given a motion that has the same direction as that of the projectile. Debate
if the head off JFK moves forwards or back, in z313, whatever, you cannot prove anything with it. Which might explain why it keeps coming around and around. There is physical proof, in 2022, that can back up the claims I am making here.

'head snap' is the vernacular of choice for those that say the head moves momentarily forward before blowing backwards. But you can use it only if Steve the drummer in a band says so. I'm just saying this 'head snap' is more conclusive than 313. And, it (z-film) clearly captures a 'projectile' striking the target. What more proof do you need?

And, i'll clarify, the version of z-film displaying this projectile striking JFK's jawline is the version extracted by Robin Unger & Martin Heinreichs (sp) from the JFK movie by Oliver Stone.
We got everything, I think we were the first people to have the whole thing, we had it steadied, had every frame: I think the FBI had cut it up - or the police department had cut it up to analyze it. Anyway we restored it, we had the entire thing - Joe Hutshing, video editor for JFK movie
Oh btw, I have some more proof!
Just to add to this mystery. Does the 'projectile' glowing white blob strike the wrist area of JFK's jacket?
Is there also a corresponding mark on the sleeve of JFK's jacket in the area where a projectile is seen to strike his right wrist?
Notice in CE393 the jacket worn by JFK has been photographed with the right sleeve (some might say, conveniently) tucked in so that the right cuff of the jacket isn't fully visible? below (I have a higher res version too)

A photo of the jacket was released (years later in the 80s) showing the right cuff. below

Clearly visible are the cuts in the jacket made by the doctors at Parkland hospital. But the right cuff area of the jacket also appears to have a cut in the fabric. And corresponds with the area to which the projectile is seen in the z-film striking JFK's wrist!

You can just about see the large blood stains on the cuff, around the area of the mark, then contrasted with the white lining below, where the parkland doctors cut.

And I guarantee there are two tiny holes on that right sleeve that would indicate a .22 caliber projectile made those holes. One of entrance, and exit. Most of the witnesses reported a firecracker sound. A smaller caliber weapon.

If anyone is fortunate to get to see JFK's coat, they will see two small holes. An entrance and an exit on the right cuff area. They are both slightly visible in the gif above. The projectile struck JFK's cuff and pierced a clump off material passing through it and then striking JFK's chin.

The z-frame above us approximately 257, shows blood or redness on JFK's jawline. JFk's autopsy photo also shows a circular indentation in the jawline corresponding to the z-film.
I have tried to get a high-res photo of the JFK jacket at the archives, but have been unsuccessful. If any one can get a close up of the sleeve. This would be very helpful.
If you want to see evidence of JFK's being shot from the front/side/conspiracy, etc, just pester the Kennedy family to see the jacket in person. It's all there!