Went to a gun show here in Memphis thish morning (Saturday, February 2nd) and saw three Colt New Service revolvers, all around $900. One was a pristine .45 Colt with aftermarket grips and an M1917 cylinder latch. Another was good shape, smoe wear in .45 Colt. And the third well worn in .455 Eley.
One was next to an Official Police .38, which emphasized just how big the New Service was. The Official Police was no slouch in size.
As I recall all Colt revolvers of the day were six-shot, and were for .38 Special Hi-Speed ammunition.