Timed while loop?

So Here is my code, now my problem is Unity is obviously designed to crash when there is an infinite loop, so how can I make a: 1. Timed loop, that goes off every .1 seconds, 2. would that still crash? if so how would I make it not? Heads up, this is the code for a machine gun.

 var c1 : Color = Color.yellow;
 var c2 : Color = Color.red;
 var lineRenderer : LineRenderer;
 var myPrefab = gameObject;
 function Start() {
      lineRenderer = gameObject.AddComponent(LineRenderer);
      lineRenderer.material = new Material (Shader.Find("Particles/Additive"));
      lineRenderer.SetColors(c1, c2);
      lineRenderer.SetWidth(0.2,0.2);
      lineRenderer.SetVertexCount(2);
 }
 
 function Update(){
 
 var origin = transform.position;
 var direction = transform.forward;
 var endPoint = origin + direction * 100000;
 var hit : RaycastHit;
 
 lineRenderer.SetPosition(0, origin);
      if (Input.GetButtonDown("Fire1")) {
      while(Input.GetButtonDown("Fire1"))
 {
 if (Physics.Raycast(origin,direction,hit))
 Instantiate(myPrefab, hit.point, Quaternion.identity);
 endPoint = hit.point;
 
 lineRenderer.SetPosition(1, endPoint);
 
 }
 }
 }