Like I said, my knowledge of ballistics - interior and exterior - is quite adequate. Just a bit presumptious of you to think otherwise..
The reason an all points bulletin was made on Oswald was he was the only one to leave work and not return and there was an eyewitness who described him to the police. The only mistake the witness made was the description of the rifle.
Oswald didn’t accomplish any work all that morning. The boxes for the sniper’s nest was constucted that morning. Oswald’s fingerprints were all over those boxes. The wrapping paper that held the fictional “curtain rods” was left in the sniper’s next.
All three shots came from the sixth floor according to the trajectories.