There is such a wealth of information about the 250 scattered over at sigforum, that I thought I would start pulling some of it over here. I'm afraid to violate anyone's copyrights, so I'm going to post links where I can, and paraphrase where the information is too diffuse across many posts.
The first one is detail stripping the 250. In layman's terms: Completely dissassembling the fire control mechanism for a good cleaning.
Thrak over at SIGForum did an outstanding job describing the process, with pictures. Link is here:
http://sigforum.com/eve/forums/a/tpc/f/150601935/m/6961064631Also check out sigfreund's followup about re-compressing mainspring when reassembling the frame:
http://sigforum.com/eve/forums/a/tpc/f/150601935/m/4851018631