I believe I used to have what you are talking about. It was actually a Snaro with a 7/8" broadhead infront of it. Never had the chance to shoot a bird with it so don't know if it would work or not. But I also believe they were intended for smaller birds such as grouse, pheasant, quail. Not as large as a duck or goose. I would guess hunting geese you would want to hunt them like turkey. Ducks...well I have no clue to be honest.