Bullet position for each client is different

So I've got a code for my simple bullet, heres a part of it

Code (CSharp):

1.         if (Input.GetMouseButton(0) && Time.time > Nextfire)
2.         {
3.             Fire();
4.             Nextfire = Time.time + Cooldown;
5.         }
6.  
7.     }
8.     [Command]
9.     void Fire()
10.     {
11.         GameObject projectile = Instantiate(bullet, bulletPos.position, gameObject.transform.rotation);
12.         NetworkServer.Spawn(projectile);
13.         var bulletscript = projectile.GetComponent<BulletDamage>();
14.         var rigid = gameObject.GetComponent<Rigidbody>();
15.         bulletscript.velocity = rigid.velocity.magnitude + bulletscript.velocity;
16.     }
17. }

And its basicly a modification to mirror tank demod code

Code (CSharp):

1.  if (Input.GetKeyDown(shootKey))
2.             {
3.                 CmdFire();
4.             }
5.         }
6.  
7.         // this is called on the server
8.         [Command]
9.         void CmdFire()
10.         {
11.             GameObject projectile = Instantiate(projectilePrefab, projectileMount.position, transform.rotation);
12.             NetworkServer.Spawn(projectile);
13.             RpcOnFire();
14.         }

so Why my code,The first one,When the host+client hit fire,the bullet will came out from the client perspective eg. if host is at 0,0,0 and player 1 is at 100,100,100,host shoot the bullet,host will see the bullet being shoot from 0,0,0 and player 1 will see it being shoot from 100,100,100,while the tank demo bullet was fire from the client position.Local player is checked