[Ben Holmes]

(40) The four cartridge shells found at the Tippit murder scene were fired from Oswald's revolver.

Chain of custody issues raise their ugly head again. I'm quite sure that many people are aware that radio transmissions from the scene of the Tippit murder stated that the murderer was armed with an automatic. This is easily determined  from the cartridges. Revolver cartridges have a rim that's larger than the case body - that stops the cartridge from moving too far into the cylinder chamber. Automatic cartridges, on the other hand, have a rim the *same size* as the case.

There are two revolver cartridges shown here - can you spot them among the automatic cartridges?

The differences to an experienced police officer are obvious and can VERY QUICKLY be determined... but this caused a problem because Oswald didn't carry an automatic.