I'm wondering what everyone uses for range bags going to and from the trap field? Specifically I am looking for something that is made specifically for storing boxes of 12 gauge shells, say 4 boxes up to a whole flat. I am tired of having a cardboard flat of shells in the back seat of my truck and walking back after each round to grab a new box of shells. Any links or names of bags/packs that you use would be great! TIA 