I have a Colt OMT, 38 spl DOB 1938, with an aftermarket hammer. When I showed a pic to Joe Miller, the US Revolver Association historian and a collector of prewar Colt target revos, he told me that he thought the hammer was a Roper. He based the comment, he said, from having seen guns with similar hammers whose owners said the hammers were received from Roper. On the other hand, Kevin has researched the heck out of Roper and has yet to come across a written reference to Roper hammers.

(I think Roper hammers are extremely rare. Maybe only two exist, the one Joe saw and the one I have! I have cornered 50% of the market! )