Never trust what you see on film--it's always misleading.
We have had access to actual screen-used stunt castings, and the tip of the "laser pointer" is square. Look closely at the screen captures in the previous posts and you'll notice that there are no sharp edges on the gun. The graininess of the film is causing the clear acrylic tip to look like a rounded LED. It is not. Trust me all ye skeptical ones.