Issues with physics and replication when colliding with a player when the server owns a part

I think this is because I put inside the server script that when the grenade is put into the workspace, its ownership was set to server automatically. But when I fling the grenade with my character the physics system seems to get confused and desynchronize.

I want the ownership to be the server’s so exploiters cannot throw it with extreme speed or teleport it to their enemies (I want the grenade to be able to detonate when it hits something with high power) but is there any way I can keep these two without desynchronizing the positions?

(I will try to comment the video onto this post, I cannot attach it for some reason)