Sorry if I was misunderstood, if you have a dragoon then go ahead and cram as much powder in it as it will hold. I was just pointing out that the 44/40 had a 40 gr black powder charge and killed plenty of deer, and I realize that the bullet was a lot heavier than a round ball and shot out of a lever action rifle, the velocity higher; still, Custer did claim to have killed buffalo (probably females) on many occasions with an Army 1860 at point blank range.
Many years ago I was sitting against a tree (I'm right handed) with my rifle resting on my lap and a buck came in on the "wrong" side- my right. The only way I could shoot it was to slowly move my rifle around and try to shoot left handed- the only trouble was I was in the thickets and the buck was only about 8 yards from me. If I had a revolver I could have taken that deer. I started to move the rifle and got it about half way and the buck took off. After that I have often carried a pistol if I am on the ground, stump sitting.