Not exactly what your looking for but maybe worth taking a look?
How to make a gunshot squib http://www.clipta.com/Backyard_fx_05_ho … 8725120289
or take a look at this http://www.instructables.com/id/Theater … ot-Wounds/ (You have to sign up to gain access to the guide and large images it’s free though).[img:b3886]http://www.instructables.com/files/deriv/FZ5/KSNB/F23Z352D/FZ5KSNBF23Z352D.SMALL.jpg[/img:b3886]