Welcome to the Forum.

You have a .38/44 Heavy Duty. It is built on the .44 frame (hence the name). It was designed in 1930 to fire a heavier .38 special load, that would penetrate gangster's car bodies, in response to Colt's Super .38 in the Government Model. The .38/44 was the daddy of the .357 Magnum, which debuted in 1935.

Yours is post WW II. I'm guessing this one was built around 1947 or so.

__________________
John 3:16
WAR EAGLE!