Well i made one These things are fookin mad ! i couldnt find the bits i wanted up b n q so made do with what they had, ended up doing it with the grey stuff as it was the only one there that had a 2 inch adapter on it for the barrel ... i did have one blow out that wasnt very funny one of the blanking blugs i put in one end shot out when ignighted and went through a garden fence panel !!! , mines workin prety good now but needs a better sparker really and thinking of doing another better + safer one ...... i been launching stuff all day useing carb choke cleener ' at its best it will thr