Another possible modification by the folks at Aberdeen.
Note the part of the gun barrel just outside the mantlet.
Every photo of the 88mm L71 on a JagdPanther that I've ever
seen has a continuous-diameter barrel all the way to the muzzle brake.
Anyone ever seen on like this????
Panzer Dan, Baron von Beergut and I figured the Proving Ground folks
had to put some of these back together with whatever parts and pieces
were at hand if the originals were missing or badly damaged, and that the
Germans had probably spiked the gun barrel of this vehicle.