Anyway to instantly spawn objects on the client?

I am trying to create a projectile on the client side, then have the server create the same projectile on all other clients. I did this easily, but realized that the client had to wait for the server to create his own projectile. This makes my game feel horrible and laggy. I've tried something new which partially works, but I get the "Object reference not set to an instance of an object" error. Everything works when creating the object on the host client with no errors and no lag, but not on...

Anyway to instantly spawn objects on the client?