Posted By:
fkwMost of the known types of Goudey reprints are usually easy to spot but I would have to see a scan to be certain. Most of the differences will be in the cropping of the photo area of the card, the width of the borders, The card stock, the ink color of the back, and the ink colors of the front.
If you can get your hands on an authentic card from the set (lower grade is OK) then you can compare the way the cards were made, surface texture, thickness of stock, print quality, ink colors, cropping, etc.
Here is an example of cropping differences in the R319 #181 Ruth card
(but remember there are many types of reprints so it is not the same for every type)
Elbow area on Reprint 
Elbow area on Authentic 
Top of Hat on Reprint 
Top of Hat on Authentic 
Frank