Hi There,
After refreshing my memory, the S&W NM#3 DA "New Model Navy"
First Model came out in 1881 and were numbered from 1 to 54668.
They were chambered for the .44 S&W Russian ctg. and sold from
stock up to 1913. The "Frontier" version was numbered in it own
serial number range from 1 to 15340.
There is a cryptic note in the Niel & Jinks Smith & Wesson 1857 - 1945 ...
on pp. 197 it says:
"Most of this model chambered for the 44 S&W Russian cartridge
had 1-7/16" cylinders but a few late ones were made with 1-9/16"
cylinders."
I have read (but cannot locate at this time) that the last of the "Frontier"
models (both single and double actions) were just rolled into the regular
NM#3 SA and DA serial range. I don't know when this took place but
I have one example SA that is numbered in the regular NM#3 SA serial
range but has the 1-9/16" cylinder. In my case, it is serial number 35722
which is within the last 100 SA revolvers made.
The OP's revolver is not at the end of the serial number range so therefore
should be .44 Russian.
Cheers!
Webb