Currently using thick cardboard boxes 19cm x 47cm leaning against the hollow of a beech tree with permanently wet mud at the bottom. Smashing loads of marbles and now I'm experimenting with different distances I'm losing a fair few as they tree hit and then land after what seems an age. Ammo catch requirements: Packs small Quiet to use Quick to set up Quick to take down Can survive getting wet Idea so far: Tree to paracord to collapsible tent pole to two guy ropes to two pegs. Drape (would a bed sheet close weave but thin be stronger/ more resilient than a towel loose weave but thick?). Tied to paracord with 3x Prusik knots at the top loosely pegged at the bottom with short guy ropes. Bottom of drape folded up and sewn to form pouch. Maybe a tack in the middle to give some support. What sort of size? How much of a margin beyond expected grouping? Now that I'm not looking to pierce cardboard I might not need such powerful tubes (but then again I am shooting 20 metres) Any ideas?