UnityEngine.Vector3 to UnityEngine.Quarternion

My script:
using UnityEngine;
using System.Collections;

public class Gun : MonoBehaviour {

public Transform muzzle;

public Projectile projectile;

public float msBetweenShots = 100;

public float muzzleVelocity = 35;

float nextShotTime;

public void Shoot() {

	if (Time.time > nextShotTime) {
		
		nextShotTime = Time.time + msBetweenShots / 1000;

		Projectile newProjectile = Instantiate (projectile, muzzle.position, muzzle.position) as Projectile;
		newProjectile.SetSpeed (muzzleVelocity);

	}
}

}

: Second last line wont work, says it cant convert.
Any ideas as to whats wrong?

Change muzzle.position to muzzle.rotation

 public Transform muzzle;
 public Projectile projectile;
 public float msBetweenShots = 100;
 public float muzzleVelocity = 35;
 float nextShotTime;
 public void Shoot() {
     if (Time.time > nextShotTime) {
         
         nextShotTime = Time.time + msBetweenShots / 1000;
         Projectile newProjectile = Instantiate (projectile, muzzle.position, muzzle.rotation) as Projectile;
         newProjectile.SetSpeed (muzzleVelocity);
     }
 }