From my understanding the earliest authentic Krag carbine serial number was 24709 or 24708 somewhere in that area if my memory serves. I also recall the early Carbines were known as prototype 1892 carbines and I always assumed they would have been done on 92' actions. How much does the gun weigh? I think there was close to a 1lb difference in weight between the early prototype and type 1 carbine vs the later type 2. Though I also remember something about a few of the really early carbines had full length stocks?? Just a long shot here but could this be an early 1892 Krag Carbine prototype or early type 1? I concede it is beyond my expertise just like butlersranger but I thought I would chime in and get educated as well :)