I ran into the same problem with my 1929 manufactured '97 even though it was in great condition.

I took it apart and cleaned it a bunch to get all the old fouling out of the action. I even dabbed some USGI rifle grease lightly on a few of the mating surfaces. She still requires a bit of arm strength to opperate BUT its a whole lot better than it was and comperable to other M97's i've handled.