I offer one I believe is a 1899 altered for knife bayonet and sling and a school gun.  I believe it is real, and invite expert criticism.
1. Ser. 342910 is a 1899 (over stamp 9).  I sent an inquiry to Martial Arms Collector (SRS).  The response in Dec 2015 issue was over stamps were rare and all 1899s were carbines.
2. Poyer on page 101 discusses the over stamp 9 on 1988s to create carbines.
3. Barrel is 22", properly crowned.  Turned down in the modification to .620" back .75" to the properly mounted Krag front sight.  Fore end lightening hole professionally plugged.
4. Rear sight is 1898 carbine sight marked with c on base and eyepiece.  Only used on 1899 carbine (Poyer p 163)
5. Two cartouches, well worn, can't read.  One the normal dimension, the other more rectangular, perhaps a referb.
6. Wear on the for end stock and barrel blue reflects a lot of drill field time at parade rest and attention.
I offer it up for comment.
Joe

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