Hi James, Welcome to this forum. We have actually been discussing your gun on Jan Still's forum (see link). It's actually a 1906 1st altered Navy with a 1917 Navy top half. The 1906 model has a longer frame than the 1917, and you can see that the receiver on your gun is set back a little from the front of the frame. Also, no 1917 Navy has a grip safety. Regards, Norm
http://luger.gunboards.com/showthread.php?t=26752