Arnold,
I had been under the impression (no pun) that the proper way of testing casehardened material was with some kind of micro-superficial testing and that Rockwell C scale testing would provide erroneous readings??? Aren't typical casehardened surfaces well above 60RC (if it could be RC measured)? 25RC seems really soft since most of the typical modern guns (4140?) I've tested were around mid 30's RC.