Hello everybody. I understand that already 2020. But still I decided to write an answer. I also had such a problem. My (Projectile) did not match on (Client / Server). The thing is that before I created (Projectile) in the world, I released (LineTrace) to indicate rotation for (Projectile). But (LineTrace) I released through (OnServer -> Multicast). That was my mistake. She decided when I released (LineTrace) for all players only on (Server). And transmitted the received coordinates (to Clients). That is, if you release (LinTrace) not on the server, then for each copy the calculations are different, because of the delay. Accordingly, the rotation for (Projectile) for all clients was slightly different.