Many years ago, some of the WW2 S&W Victory models chambered for the British .38/200 round (.38S&W essentially) were brought back to our shores. Some importers had the cylinders bored out to accept .38 Spl and marketed them as Spls. Fired .38 Spl rounds would over-expand slightly, but the gun was safe enough with 158 gr service loads. No +Ps back then. This type of gun was used to kill Officer J.D. Tippitt after the JFK assassination.
You probably don't have one of these, but FYI.