RamscoopRaider
Donor
Union Barrels we know from canon were the A7V esque Mark I, a Mark II "Custer" with a 50mm in prototype, 37mm in production version and a 60mm armed stopgap during SGW, then we have the Mark III present in most of the later books, with a 90mm gun and heavy sloped armor seen after encounters with the 75mm armed CSA Mark IVIdeas for the Union barrels. The descriptions of them definitely leave out the M4 Sherman. I always thought the main barrel would be somewhere in weight between the Sherman and the M3/M5 Stuart family.
It has a similar history to where the first model was lighter with a 37mm gun, the second model was updated with heavier army and a heavier gun.
http://www.tanks-encyclopedia.com/ww2/US/m7-medium.php
Or maybe the M24 MacArthur (name would have to be changed), credit for this design goes to joshshapiro of deviantart
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