I am going to buy a new shotgun for waterfowl but I am not sure if I should go with a 10 gauge or 12 gauge? I currently have a 12 gauge Remington 11-87 that I use for small game. Is the ammo for the 10 gauge hard to find and a lot more expensive? Does a 10 gauge have that much more range? Is 10 gauge available in 3 inch?