I recently purchased a Colt Detective Special on an auction site and when it arrived, as I always do; I checked the gun and found that the timing was off in double action, when pulled into single action fast, the cylinder failed to revolve. After taking it apart, I found that the hand had been filed too short (Top) and that the trigger pin was loose. I obtained replacement parts from Numrich Gun Parts and when they arrived set down to custom replace these parts. As all colts are made by hand, they have to be repaired with a temper as a watch repairman is since the parts have to be hand-fitted. Fortunately, I listened to many of you in this forum and got a copy of Jerry Kuhnhausen's book on The Colt Double Action Revolvers shop manual and discovered exactly what needed to be done to the new hand that I was replacing, and at which points the hand needed to be fitted. I replaced the trigger pin and finished the hand and when I tried it and followed the directions from the manual it works perfectly! I highly recommend to anyone who has decided to do gunsmithing on their own with a Colt Double Action revolver, to get a copy of that shop manual from Jerry Kuhnhausen...it is a life saver.