After a revision when it was thought to be machine doubling, it was then classified as a RPM. However, the MM was slightly left and the doubling was on the left inside of the O. Your MM is in the normal position and one can only surmise that because the anomaly is inside the right side of the O on your coin, it is machine doubling. Check these images http://vamworld.com/wiki/1885-O_VAM-12
Thanks for the help. Any thoughts on the BUS area? It also has the same surface/look on the reverse in the same area.