Hi folks
Father in law has had this in his attic for ever and would really like to know a bit more about it and possibly a valuation.
http://i864.photobucket.com/albums/a...psjb9rorqh.jpg

The only markings I can make out are

Colt's PT FA MFG CO HARTFORD CT USA
Patented May 29 Sept 18 83 MAY 26 85 JUNE 16 86 FEB 22 87

Thanks in advance.