I lent my son-in-law my m1903. He shot a few rounds, then took it apart to clean it. He said his friend "probably didn't put it back right" Now I can't get the bolt open in normal operation. Something is stopping it. To get it open -- I have to cock the gun by pulling the firing pin knob and rotate the safety up (mid position) then operate the bolt to open. I just can't figure it out ... any help would be appreciated. Bill