I have confirmed this on Everon at this specific location. I have tested other locations that are similar, having a sign at the end of the rail. So far this is the only location it happens.

To recreate...

Load Game Master Everon.
Create player in Saint Philippe at Grid 045 108 next to the sign icon for crosswalk. (see image)
Fire rounds between sign and end of curved down rail. (see video)
Rounds collide in midair. Player cannot walk through that area but can vault over.