And in theory, that's all you should need. Please keep a scenario like this in mind: You get off a not so great shot at a deer and it runs off. You then wait a bit and start to track after you reload your gun. You see the wounded deer in front of you but it's a little far off so you try to get a little closer. As you do, the deer senses or sees you and starts to hobble or trot off and you shoulder your gun to take a shot and you miss. You see the deer stop and rest again, but you are now don't have another load. A similar experience happened to me when I accidently only took two rounds out with me years ago with my shotgun. When I got to my stand, I figured one shot is all it takes, right? Lesson learned.
Fortunately, my story ends up with a happy ending. I back tracked and found an Amish boy who was hunting the same woods. He gave me one sabot (I was shooting regular slugs.) and I wnet back to where I finished off. I ended up spending the next hour circling around him and snuck up to within 20 yds in a swamp, with him still facing where he had run from. Turned out to be a decent 11 pointer and a hard lesson learned.

Mike