'Wizard' - I find the SRS data rather frustrating, because there is very little context.
It is just a quick 'snapshot', indicating a specific serial number was found listed in a surviving official document, from some point of time.
It is all rather arbitrary, because lots of material has been lost or was never reviewed.
The nature of the source is not mentioned.
Whether the current owner, (of the SRS data and Frank Mallory's research), has more background information, I do not know.
Some quick internet searching shows, that in 1920, the U.S. War Department organized the Regular Army, Reserves, and National Guard into nine Corps Areas.
The attached description identifies the extent of the Second Corps Area.
(My hunch is that the SRS mention of model 1899 carbines in 02/19/1936 was possibly related to one of the cavalry groups in the Second Corps Area? Just a guess, I don't rightly know).
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