The pix shows a freeze frame taken at 13:25 from the Secret Service re-enactment video on youtube named -- JFK Assassination Recreation - Kennedy Reenactment - secret service warren report – this footage is on a site belonging to videohavoc & is 24:46 long. It shows a limo passing under the signal arm as seen from the 6th floor window.
I have drawn a star showing a possible aim for Oswald's first shot at say Z123 of the Zapruder film.
Actually the relevant Zapruder film sequence starts at Z133, which is about 10 ft or say 10 frames later, but i will call this freeze frame as being at Z123 anyhow. As can be seen if the shot were a frame or two earlier then that bullet would have ricocheted off the signal arm at about the collar or rod or pipe. The limo in the freeze frame is probly a foot or two further from the far kerb than was JFK's limo.
I reckon that the ricocheted bullet fragmented.
And the main remnant lead slug made a non-round hole in the floor
(shown by a star).
And it made 2 mainly copper fragments (CE567 CE569)(not shown here).
And it made a spray of small lead pieces some of which lodged in the back of JFK's head
(shown by a star)(lead pieces show in Xrays).
The star on the windshield shows the pozzy of a dent (in the chrome trim) which was made by one of the 3 or 4 shots fired by Hickey's AR15 at Z313.
A crack in the windshield just left of & below the dent was made by the remnant slug that exited JFK's head from a shot from Hickey's AR15 at Z313.
JFK's limo was longer than the limo in the pix, & had jump seats, & the hole was probly in between the jump seats. We don’t know the hole's exact pozzy. If u go to the Ford museum & have a look under the limo u might be able to see.
The fragmentation of the FMJ slug in Oswald's shot-1 is identical to the fragmentation found in replication/tests. The remnant lead slug takes a small deflexion, & typically the copper jacket breaks into 2 fragments which take a wider deflexion whilst staying close together. The tests did not include a measurement of the spray of small lead pieces, but i think that a concentrated spray mostly taking a very small deflexion angle (& hitting JFK on the back of the head) is reasonable.
https://sites.google.com/view/oswaldsfirstshot/homehttps://photos.google.com/share/AF1QipPNYhsVvFb7NjNyOvPCyTnGtmP3XpWWM2GN9PYxT-RiaYBjC1sygstEOSKU718Jyg?key=bmtZbEUzbERLb3l4TW5aeFBrem5tS1dzZVVuNm9B