Radial Blur Shader in Unreal Engine 4

Today I've made this simple post process material, that applies a radial blur to screen. That was made for a sniper rifle mode in game, when player is looking through a optical sight. And we've got this raw effect:

 

To create this shader I use a custom node expression in material editor. You can see it's code here:

Just copy the source and paste it into your custom node.
Modify as you need.