think ridiculously over-sized super soft barrel condom. well, more or less. fabric hood/cone/snake/sock is the way to go. I experimented with the kind of mesh that upon reacting to force proportionally tightens up, conversely expands, but never really got very far with that (lots of potential, I just never followed up given how well the fabric snake sock thing worked). I found shooting lots of balls, at high rof, would generally promote breaks in the collection device, but I don't know if this is a universal rule or just applied to my socky thing.