I assume you have it ricocheting off various tree limbs and traffic signals in order to reach the manhole area.
No, actually I believe that the first shot was inadvertent due to interference from the conduit closest to the window. It appears to me that the shooter’s left elbow would have been very close to it when he brought the rifle up and began his aim. If his left elbow actually struck that conduit while his other finger was on the trigger, this interference and resulting sudden stop of the movement of the rifle could have caused what is termed an accidental discharge by gun safety instructors. Because he likely wouldn’t have wanted to let anyone below see the rifle ahead of time, I believe that he would have waited until the limo was below him and then been in the process of quickly bringing the rifle up into position for an intended first shot as soon as the target emerged from under the tree limbs cover. Since he likely wouldn’t have been able to physically practice this maneuver (with the rifle) ahead of time, without potentially drawing unwanted attention to himself, he likely wouldn’t have anticipated the interference from the conduit. I believe the inadvertent shot happened before the rifle was fully aimed and that the bullet simply traveled to the manhole cover area without hitting anything beforehand.
Others have theorized the interference from either tree limbs or the traffic signal as reasons for the first shot missing the limo entirely. But the evidence for those scenarios is slim. The theory I believe in explains why the shot missed (it was inadvertent and thus not fully aimed).
As I'm sure you're aware, there is not even the slightest hint of any evidence to support your belief. It is completely a matter of faith.
It makes sense (to me at least) that the assassin would want to get off a shot far earlier than my proposal of z223. I also accept that, for some reason, the assassin chose an unnecessarily cramped spot to take the shot from (he had the whole sixth floor to choose from). What you propose is not beyond the realms of possibility.
My first problem is the difference between the position of the limo in the z130's and the manhole area. Was Qswald swinging the rifle round in a big arc in order to take aim? The difference between the two positions is radical and I cannot envisage how he can be holding the rifle in such a position as to accidentally shoot so far off the mark.
Obviously, my second problem with a shot so early has been discussed elsewhere in depth.
Your theory would also work for the manhole cover strike scenario if the third shot was the one that missed. However, if that were the case, I believe that more witnesses would have described a shot after the headshot in their accounts. Most witnesses seem to believe that the headshot was the last one.
"Most witnesses" do not believe the headshot was the last shot.
Some do and some don't .