Keep in mind the reverses of the
ATB (America The Beautiful) quarters has an incuse design on the outside circle of the coin. This incudes the date and the descriptions. When
Machine Doubling happens on incuse designs, the devices can suffer from die movement leaving the devices looking but doubled. But this is an illusion. The machine damage makes the devices look wider/taller and on raised devices would indicate hub doubling. But when the devices are incuse, the opposite happens. The raised devices from the die move slightly and enlarge the devices from a normal die. If you saved a roll of these from circulation, you will find a large percentage of the quarters suffer this machine damage. Here are a few examples:


The bounce during the strike makes these devices distorted. It is not on the die, but caused during the striking process.

Note the arrows showing these devices as raised from the die. (opposite what creates a raised device on a coin) the raising of the devices on the die makes the devices press into the
coin.
Here is a side by side of what a normal die and one that is showing machine damage looks like.



More example of MD on the incuse devices:




Save a few examples you find in circulation into a tube and you will see what I'm talking about with the MD on these incuse devices.