4 inch barrel curious & relic acceptable.
It was "made that way" and military issue in between 1910(in spite of being accepted in 1908
) and 1942.
These were not altered in anyway.
There are not many things more "curious & relic" than these.
Almost as recgonizabled World wide as the Colt Single Action Army. And more than the 1911(World wide I mean
)
Top to bottom. Made in 1916, made in 1938, made in 1941.
So, it is cannot be because of barrel lenght. Unless it's not in it's original configuration.