A lot of these coins are damage from a couple different things. I'm not home, and I think I threw them back into circulation anyway, but these coins are from roller damage or coin machines like candy or ect. Mostly rolling machines like those that crimp the ends like a bank roll. For some reason it's usually on 7 ' s and 1 ' s but I have seen examples on 2 ' s and 4 ' s as well. Also sometimes in worse cases you see damage on the L or I in liberty. Looks like the top picture on this page may have suffered some damage. If the coin had just had it happen or hadn't been circulated after the damage you would probably see more signs like a scratch or gouge going around the whole coin. But circulation and wear takes those minor nicks away. Coop probably has some good pictures of examples but I don't keep records as good as him.