It used to be a 1911 Commander, but I now occasionally carry a Super Blackhawk .44 Magnum with a 4-3/4" barrel.
Usually carried in a "Tanker" shoulder holster, but occasionally OWB in 4 o'clock position. The short barrel makes it just a little bit longer than a 1911. And, of course, it doesn't have the 1911's flat profile.
Under a rain parka, it's concealed. More by accident than design, but it's still concealed...