This means that there were at least four shots that grim November afternoon. Law enforcement's inability to account for those additional bullets would not mean they do not exist; only that law enforcement cannot account for them.
So, why were no other bullets found?
Actually, parts of several bullets were found. There were large bullet fragments on the floor of the limousine, a bullet found 300 feet down range from the TSBD; evidence for potentially as many as ten different bullets. I believe that some of these indicators, such as the dented chrome above the Presidential limousine's windshield, and the hole in the windshield itself were from bullet fragments.
I believe that only five or six of the indicators were actually caused by independent bullets, the rest were caused by bullet fragments.
I also believe that one or more of the other assassins were probably using some form of frangible or explosivebullet, like the mercury tipped ones described in Frederick Forsyth's book The Day of the Jackal. Or some devilish design out of the CIA's Science and Technology Directorate. With their "explosive" capability, and the fact that they shatter into a thousand unidentifiable pieces on impact, they are the perfect weapon for a sure kill that cannot be traced.
If there were at least four shots, then there had to be (by the Warren Commission's own logic) at least two gunmen. If there are two gunmen, that makes it a conspiracy, something that the National Security State did not (and I suspect even today does not) want properly investigated.
So let us quickly recap:
The loss of material in CE 399, the so-called "magic bullet," almost certainly cannot account for all of the bullet fragments in Governor Connally's body, since two of those fragments alone account for more than half the lost material.
There is no evidence that CE 399--or any other bullet--ever traversed the interior of President Kennedy's upper torso from the back to the notch of the throat. This is because of the failure of the doctors (at the behest of their superiors) performing the autopsy to fully probe or dissect the wounds in the back and the throat to see if there was a wound track consistent with the theory. In fact the best evidence we have is that they are two completely separate entry wounds.
If no bullet passed through President Kennedy, it could not have continued tumbling onward to hit Governor Connally. This means an entirely different bullet hit Governor Connally from the rear. The short period of time between the round that hit Kennedy, and the one that hit Connally, makes it impossible for the shot that hit Connally to have come from the Mannlicher-Carcano rifle. This means that there were at least two assassins with rifles behind the President's limousine. This--together with the throat wound--also proves that there had to be at least three assassins/teams in the kill zone at Dealey Plaza that day.
The National Security State apparatus had decided JFK must die, and gathered a large group of JFK's enemies to accomplish different parts of the task. All they had to do then was open up JFK's security net, and permit the perpetrators escape.
So let me give you a brief synopsis of what I think happened that grim Friday in November, after the Presidential limousine turned on to Elm.
The sniper on the sixth floor of the Texas School Book Depository (from this point forward Sniper 1), using Oswald's Mannlicher-Carcano rifle fires a shot at JFK and misses. Whether or not this is actually Oswald is a question for someone else to answer, but if this bullet hits and kills President Kennedy, it creates an air tight frame on Lee Harvey Oswald.
Sniper 1 takes his second shot at JFK, hitting him in the back, center mass. However, the propellant in that cartridge had degraded over the previous twenty years, so that rather than a kill shot, the bullet only penetrated 3-4 inches into the President's back.
A sniper in front of JFK (Sniper 2), whose orders are not to fire unless the first two rounds fail to kill JFK, fires a round using a rifle with a sound suppressor and explosive/frangible ammunition. This round hits JFK in the throat, which the assassin knows (from experience) may or may not kill the President.