Not for nothing. (it's a Jersey term) Pronounced NOTFurNutin as one word hence the term rather than phrase.
I just have to ask the silly questions as I can not see how you installed the scope.
But does the extension or the hammer hit the scope in any way, shape, or form?
even a light brush can create a FTF.
Moving the extension under the hammer or repositioning the scope back a little may fix the problem before you take a drill, file or saw to parts.