Mike, Without the serial number, I'd have to rely on the old style lockwork. The rebound lever stud is present in both drawings. The straight 1905 had this type system, BUT, it had a different cylinder stop and trigger.
The date of the poster suggests that the round butt depicted was indeed a 1902. Subsequent posters suggest that the Model 1902 was available for, at least, another decade. There's no way of knowing how many thousands of 1902 models went unsold, collecting dust in the company vault. That does not mean, at least to me, that every round butt revolver was a model 1902, or every square butt revolver was a Model 1905.
To ignore the only sources of information (i.e The text books referred to above) is to ignore all of the remarkable research of their authors. To do so based on artist depictions on sales brochures does not have a common sense appeal. Re-writing history is okay. People do it all the time. I just believe that the sales brochures are not the Rozetta Stone that some of us think they are.
The serial numbers, the dates of production, and the engineering changes are the best source of identification of these old guns. That's my two cents, anyway. I didn't mean to get long winded on you, but you asked if anyone could tell you why they think….
