Lloyd3,
There is one problem That can't really be fixed, and an old iron frame hammer drilling is the most likely to be afflicted by it. Be sure the action has not been cracked and welded back together. By the German Proof Law, I believe if such a gun is submitted for "repair" or Reproof it will be rendered un useable. Another problem that has to be guarded against is loose coming ribs. You should "tap" along all three ribs with something hard (I use my pocketknife bolster), loose places will identify themselves by a "hollow" sound. A minor place can be repaired, but significant looseness may be a real problem, requiring relaying the ribs. A job like that won't be accepted by a German gunsmith, but one would likely replace the barrel with a current caliber one and the ribs would automatically be replaced. The cost would likely exceed the cost of a good used one. The normal way to tighten a drilling up is to replace the hinge pin with a larger one and refit it. A "cheap" temporary way is to expand the old hinge pin, stretch the forearm iron, close in the sides of the action. This requires experience, may cause worse problems and at best will not last long. Sometimes we find user installed shims. Members of this board have experience with welding a d refitting, maybe one of them will weigh in. Most other problems would be about the same as repairing an American double, except parts are not overly available. I am a big proponent of drillings and also 9.3x72R so don't let me scare you off.
Mike
