As I'm looking at the help that I am getting here and factoring in the bullet that I found on the ground, I think that chamber number 6 was unfired and it was the 5th round that was indexed. The brass looks fairly clean on chamber 6 and thinking of the way the cylinder indexs, it makes sense because that would have been the next chamber up for the firing pin. And on top of that, the cut in the bullet on the ground matches up nicely with the frame if the bullet was propelled forward while still in the "on deck" cylinder hole. There is also an odd cut in the cylinder wall between the round that was indexed and the brass from the previous fired round. Who knows...