French to English Tech/Engineering Military / Defense Ammunition

The term appears in a list of possible malfunctions that may occur during firing tests. Other items on the list include:

Perte totale ou partielle du fond d'alvéole
Rupture ou fente transversale de l'étui
Fente ou rupture du plateau
Balle demeurant dans l'âme du canon

I know that the "extracteur" is the extractor that removes used cases after firing, but I don't know what is meant by "franchissement". The malfunction is mentioned on this website:

http://www.milsurpafterhours.com/bb/viewtopic.php?f=4&t=670

But with no explanation of what it consists of. Any help would be appreciated!