what is this gun?

[mrerick]

HI Jim, and welcome to the forum.

Post color pictures if possible. Your Luger appears to be all matching and in original finish, which makes it collectable.

You'll need to check the toggle train parts to confirm that they match, and look for the number inside the trigger plate (it should be "77"). If you remove the grips to check their internal markings, do so carefully. It's very easy to break them near the safety lever on the left side of the pistol.

As mentioned, photograph the magazine including it's base from the bottom and the side.

Check with your Father in Law to see if he still has the "Capture Papers" that authorized him to return to the USA with the pistol. They add to the history of it.

Marc