So my friend and I got bored one day and decided to create this beauty...
Since the grip has a slot in it we were able to get a small square nut inside of it to tighten it.
Before we did this however, we made a SL-68 II: Vuvuzela edition. It was pretty cool/funny to use but not practical at all... and super loud. We determined that we could start a woods game just as good as an air horn.
Here is us shooting the vuvuzela edition
(warning: bad camera phone)