Well the easiest way is by the serial number but if your asking if there is a way to check a low numbered rifle then I'm not sure if it could be done without destroying the rifle. I'm no metal expert but I'd expect one would have to take a cross section of the metal and examine it under a microscope to see the metal composition and that would entail cutting the rifle.

The good news is your Springfield rifle serial number 692,8xx dates back to 1917, right smack in the middle ofWWI which makes it more desirable. What is the date on the top of thebarrel just below the front sight? That along with the serial number will let you know if the barrel is original to the receiver.