Re: Springfield Model 1896
It looks like a real carbine, but better pictures would be needed to be sure. All Krag carbines had 22" barrels, so any other length was an alteration.
There were serial number ranges where more carbines appear, but there is no way to tell from the number if the gun was made as a carbine. The receivers were made and finished, then put on the shelf until needed for assembly. If the next orders were for carbines, carbines were made; if for rifles, rifles were made, without regard for which receivers were picked.