//scripta.cs

[System.Serializable]   //I want this variable to be seen in the editor. Current value set to 20.
public class MyClass
{
    public float myVar;
}


//scriptb.cs

public class BulletControl : MonoBehaviour {

    public MyClass instance;

    void Start () {
        Debug.Log (instance.myVar); //Logs 0.
    }