Originally Posted by mike from philly
The bounce explains the inconsistent ejection pattern since movement of the shooter differs between shots. Sometimes they are holding firm other times they are moving. Each of those movements affects when and where the case bounces.
I'd bet that if you put the pistol in a vice, it would eject perfectly because the pistol is static (that may GLOCK's method of testing by the way). Use the pistol in an dynamic way, and you'll end up with odd bounces.
That is a very interesting analysis.
As with bump firing, I wonder if an astute shooter can get it to consistantly eject in a certain pattern.