Indian head and LMC with blank reverse

yup, you're right, no rim. I noticed this before and thought that being black planchets don't have rims if it was caused by two entering the press the reverse wouldn't have the rim. Although I just held the lincoln next to a normal lincoln and the one missing the reverse seems thinner. When I rolled them the entire thickness was about as thick as the thinnest edge of the normal cent, if that makes any sense. Sorry about not posting pictures, but I didn't want to go through the trouble if this is obviously PMD and mint error missing reverse cents just plain do not exist.

The first thing to do with any coin that has no design on one side is to weigh the piece. If it is under normal weight tolerance, you can rest assured that the coin was ground down to remove the design.

The other tell-tale sign is that the coin is struck on one side but has no rim on the other side. This is impossible.