El Phantasmo that is very likely a San Antonio Police Dept revolver that was standard issue in the 1970s. Prior to the .41 magnums officers here carried model 10s loaded with standard pressure .38 ammo loaded with 200 grain bullets. Here's a little history on the .41 magnum era with the S.A.P.D. An unfortunate incident occurred in the early 70s in which a patrol officer pulled over a car full of armed robbery suspects. A gunfight ensued and the officer was fatally wounded. He managed to empty his cylinder into the back window of the perps vehicle as they fled before he succumbed to his wounds. When the suspects were later apprehended, it was discovered that not one of the 200 grain .38s pierced the back glass. The .41 magnum was soon phased in hopefully to prevent this from happening again. Around the same period, the department, like many others around the country, started hiring more female officers who often had difficulty handling the large N-frame revolvers. The answer to that problem was the adoption of the model 65s loaded with full powered magnum rounds. When I was hired in the mid 80s, I heard a lot of the veteran officers talk about how much they would like to still be carrying those .41s. I have a Highway Patrolman that belonged to a deceased relative and former member of the San Angelo Police Dept. who retired from that agency in the late 1970s. At that time they were carrying .357s. I'm open to correction if anyone knows differently.