After you look at some meaningless visual pattern for awhile you can think you're seeing something intentional. Perhaps this is what's going on here but it does look to me when you blow-up the photo of the left side of the gun and photo-edit it there is writing:
In the square of color, looks like "NE" with a column of other smaller letters the the left of that:
O
A
O
etc.
On the other hand, it's getting late.