Its difficult to see how the bullet could have deflected this much going through JFKs head.
Could he have been hit higher up in the head like the HSCA suggested? This would make it easier for the bullet fragments to exit the head at the front.
It doesn’t matter where the bullet enters. The fragment is coming down at an angle, relative to the limousine, of about 13 degrees.
The highest fragment will travel about 80 inches forward, and need to climb about 9 inches, to clear the windshield frame and visor. Trigonometry says its upward angle, relative to the limousine is 6 degrees. So, the bullet fragment needs to be deflected upward by 19 degrees. This is true of both an EOP entrance and a cowlick entrance.
A lower, EOP, entry wound gives more length, through the head, to deflect upward, meaning the curve would not have to be to abrupt. It could be curving gently upward throughout the entire 6-inch passage.
A higher, cowlick, entry is harder to see. The fragment would have to hold a straight line, then, once it reaches near the level of the exit point, curve abruptly upward, by 19 degrees within a couple of inches.
Seems easier to by deflected by 19 degrees within 6 inches then it does to do so within 2 inches. Larry Sturdivan favored the EOP entry partly, I believe, because from his experience with ballistics, the amount of curvature required is more in line with the curvature he observed in ballistic gel caused by bullet fragments in the various tests he witnessed.
By the way, the bullet fragments being deflected by up to 19 degrees is no great surprise to any ballistic expert I ever heard of. When a bullet fragments, the irregularly shaped fragments will curve a lot more than an intact bullet. Which is why the fragments from the headshot at z312 curved a good deal more abruptly then the largely intact bullet that passed through JFK’s neck and Connally’s torso.