Mesh (Reticle) with Overlay shader disappears at certain camera angles

Hello guys,

I have a problem here, my custom reticle for VR game seems to disappear when the camera changes it's position. Why is this happening and how I can fix this?

Unity version: 5.3.5f1, iOS deployment target.

GIF: http://www.giphy.com/gifs/3oEjHHwvZ1gDZxANpu

Reticle shader source:

 Shader "Game/UI/Crosshair Textured Overlay"
 {
     Properties
     {
         _MainTex ("Texture", 2D) = "white" {}
         _DistanceInMeters ("Distance In Meters", Range(0.0, 100.0)) = 2.0
         _ScaleX ("Geometry Scale X", Float) = 1.0
         _ScaleY ("Geometry Scale Y", Float) = 1.0
     }
     SubShader
     {
         Tags { "Queue"="Overlay" "IgnoreProjector"="True" "RenderType"="Transparent" }
 
         Pass
         {
             Blend SrcAlpha OneMinusSrcAlpha
               AlphaTest Off
               Cull Back
              Lighting Off
               ZWrite Off
               ZTest Always
 
               Fog { Mode Off }
             CGPROGRAM
             #pragma vertex vert
             #pragma fragment frag
             
             #include "UnityCG.cginc"
 
             struct appdata
             {
                 float4 vertex : POSITION;
                 float2 uv : TEXCOORD0;
             };
 
             struct v2f
             {
                 float2 uv : TEXCOORD0;
                 float4 vertex : SV_POSITION;
             };
 
             sampler2D _MainTex;
             float4 _MainTex_ST;
             float _DistanceInMeters;
             float _ScaleX;
             float _ScaleY;
             
             v2f vert (appdata v)
             {
                 v2f o;
                 float4 vertexOut = float4 (v.vertex.x * _DistanceInMeters * _ScaleX, v.vertex.y * _DistanceInMeters * _ScaleY, _DistanceInMeters, 1.0);
                 o.vertex = mul(UNITY_MATRIX_MVP, vertexOut);
                 o.uv = TRANSFORM_TEX(v.uv, _MainTex);
                 return o;
             }
             
             fixed4 frag (v2f i) : SV_Target
             {
                 fixed4 col = tex2D(_MainTex, i.uv);
                 return col;
             }
             ENDCG
         }
     }
 }