[Jordan Baker]

I've seen some home made ones done up to fit the No4 mk1 rifles. A standard spike bayonet was cut down. It acted as the weapon mount. The cup was made from a piece of cut down exhaust pipe available from an automotive store. The ones I've seen were an adaptor piece. The larger end would just fit a tennis ball. Just below the depth of the ball a bolt was placed with a washer welded on. This was needed to diffuse the blast from the blank. In all it looked decent and could launch a tennis ball about 60 yards or so depending on wind.