Pictures would help in this case. Serial numbers ran from 1 in Sep 1917 to 163600 in Jan 1919. There should be a serial number stamped on the underside on the grip butt as well as the lanyard ring. If not, the hole was likely filled in and the butt ground smooth. For an early example (below 42000 serial number) the initials GHS as well as US ARMY MODEL 1917 and US PROPERTY stamped on it. This is assuming the frame is original.
I would limit loads to standard factory pressure ammo. No hot loads, the gun is, after all, almost 100 years old.