Given that it's a Model of 1902, the presence of the "flared tapered" barrel, says it's a 1st Change---the only "Change" there was. And it's a 1902 if it's a 4 screw frame. Otherwise (if it's a 5 screw), it's a Model of 1905 or a 1905 1st Change (the dual caliber marking being gone for good in the 2nd Change which came about in 1909).

And Absalom is right, for more "specificity" (great word, that) the serial number is needed---but of course you already know that--just like you already know about the screw count. And given you already know these things, one has to wonder why we're obliged to be talking about them-------Hmmmmmmmm??

Ralph Tremaine

Sitting and staring (INTENTLY) at the photos, I'm inclined to say it's a 5 screw frame--but I'm not inclined to bet much more than maybe a nickel on it.