Only one of the back-of-head fragments was in the galea (the McDonnel fragment).
I believe I've explained to you before the various problems with your guy-rod-deflection theory, such as the fact (1) that the angle of fire would have been virtually straight down, (2) that no gunman would have fired when an obstruction was near his target in his field of view, and (3) that JFK shows no signs of reaction until long after your posited guy-rod-deflection shot.
I do agree with you that the galea fragment could only have come from a ricochet fragment, but that fragment could not have come from a bullet fired at Z105. The lone-gunman theory has no bullet that could have produced such a ricochet fragment.
The Hickey-shot theory is nearly as problematic as the lone-gunman theory. No one who was in Hickey's car, including Powers and O'Donnell, heard Hickey fire a single shot. Have you ever heard an AR-15 fired? I have. The other occupants in the car would have heard Hickey fire a shot, if he had fired one. Plus, Hickey's ammo was checked and accounted for after the shooting.
My calculation of Oswald's angles based on above is .....
Shot-1 at Z113 is -34.8 deg. If at Holland's Z106 it is still -34.8 deg koz either way it is at the signals.
Shot-2 at Z218 is -21.0 deg.
Shot-3 at Z312 is -16.6 deg (but there was no Oswald shot-3).
So, how is 34.8 deg "straight down"?
34.8 deg is only 13.8 deg more than shot-2's 21.0 deg!
Kellerman heard jfk say my god i am hit at say pseudo Z120.
And Towner footage shows jfk with his right hand high up near his head (ie possibly reacting to getting hit in the galea) at about Z113. Alltho i suppose that jfk sometimes held his right hand hi up when waving.
Re the galea fragment, i thort that the xray showed a number of fragments in galea. But i have not spent time trying to understand the xrays. I simply quote others. Certainly u know more than me re xray stuff.
Are u referring to the 6.5 mm circular fragment? Its strange that this is the same dia as a Carcano slug. I believe that it is possible to get a Carcano bullet that has a brass end on the tail of the slug (in addition to having a brass jacket), in which case if that brass-end tears off (ie due to ricochet) then it could give that kind of fragment.
I did see a target board that showed how a Carcano ricochet off pipe gave 3 angles. Remnant slug took one angle. 2 brass halves of FMJ took another angle. And lead splatter took another angle.
All of which confirms a ricochet off the signal arm or guy-rod.
All of which confirms CE567 & CE569 (2 brass halves)(FMJ is made in 2 halves fused together to receive the lead).
All of which confirms xray splatter in galea.
But i cant find that photo of the target board. I think it is in the NOVA youtube. Would cost me $4 to do a screenprint.
That Hickey fired an autoburst is a certainty. That SS Agents etc in Queen Mary heard it is a certainty. That they lied is a certainty (except that Powers did not lie)(Powers chose his words carefully, he merely said that if Hickey fired then Powers would have heard the shot(s), which is a fact, but the inference that Hickey did not shoot is of course a lie).
Re the sound of an AR15. I wonder whether a 12 gauge shotgun is louder. I have done a bit of duck & rabbit shooting with shotguns.
http://www.sandv.com/downloads/0908rasm.pdfhttps://www.cdc.gov/niosh/hhe/reports/pdfs/2002-0131-2898.pdfAnyhow, not only did Hickey shoot a president out of season without a permit (he should have forfeited his AR15) , but he was not wearing earmuffs (he should have been fired from the SS).