Warren Commission Exhibit 616, a photograph of the base of a bullet cartridge showing firing pin markings. Scanned from Warren Commission Volume XVII.
One of the strongest pieces of evidence implicating Oswald is Commission Exhibit 399, a bullet whose markings conclusively prove that it was fired from the "Oswald rifle" found in the Book Depository. But was this bullet involved in the assassination? It was not found in Kennedy or Connally's body or in the Presidential limousine--instead it appeared on a stretcher in Parkland Hospital after the victims were brought there. Was it planted, perhaps even by Jack Ruby himself (Ruby was seen there by journalist Seth Kantor)?
Other aspects of the firearms and ballistics evidence follows the same maddening pattern, whether the subject is the Mannlicher-Carcano rifle, the shell casings found on the 6th floor of the Book Depository, the paper bag purportedly used to carry the rifle into the building, or the casings found at the scene of the Tippit shooting. The "hard evidence" in this case turns out to be rather spongy.
Besides rifle markings, ballistics evidence can be subjected to spectroscopic or neutron activation analysis, to try to determine whether fragments came from the same bullet. The FBI conducted spectrographic tests but then suppressed them. NAA tests, employed by the HSCA, remain a matter of controversy.
Blakey's "Linchpin": Dr. Guinn, Neutron Activation Analysis, and the Single Bullet Theory, by Wallace Milam.
Finding the Magic Bullet, by Lisa Pease.
The Single Bullet Theory, by John McAdams.
Ten Reasons I Reject The Single Bullet Theory, by Michael T. Griffith.
The Magic Bullet: Even More Magical Than We Knew?, by Gary Aguilar and Josiah Thompson.
Tracking CE 399: The "Stretcher Bullet" and the Case for a Dallas Conspiracy, by Jerry McKnight.
Frazier Speaks, by John Hunt.
Neutron Activation Analysis and the John F. Kennedy Assassination, by Kenneth A. Rahn.
The Magic Fragments and Other Stories, by Milicent Cranor.
Governor Connally's Wrist Wound and CE-399, by Clint Bradford.
Breakability: CE-399 and the Diminishing Velocity Theory by John Hunt.
Primary Sources: Mannlicher Rifle, by Spartacus Educational.
Basic Training: The Italian (and Japanese) 6.5mm Mannlicher-Carcano, by Craig Roberts.
The Gun That Didn't Smoke, by Walter F. Graf and Richard R. Bartholomew.
The Guns of Dealey Plaza, by John S. Craig.
An Examination of the Presidential Limousine in the White House Garage, by Pamela McElwain-Brown.
Warren Commission Report and Testimony:
HSCA Firearms Panel Report. HSCA Report Volume VII, p.353.
The Missed Shot = 100% Proof of Conspiracy. This page uses words and pictures to debunk the idea of a missed shot at Zapruder frame 160 hitting James Tague.