My favourite Nerf gun at the moment would be my Big Bad Bow/Maverick integration:

The Big Bad Bow has a PVC coupler on it. I most often use a 8-inch 17/32" brass barrel inside of PVC pipe. I think something might be a little off with it though, I need to open it up again and add a new spring/o-ring.
Also, my best nerf guns can shoot around 120+ feet.