Sorry I haven't monitored this message board for some time.
I can't remember the reference for my prior remark regarding the type(s) of carbine the 12th Missouri Cavalry was equipped during the expedition - probably from a reference work on carbines of the Union cavalry. I did review the published diary of Lt. Charles H. Springer, Co. B, 12th Missouri Cavalry ("Soldiering in Sioux Country: 1865," edited by Benjamin Franklin Cooling, published 1971, Frontier Heritage Press, San Diego, California). Springer stated he had a Spencer carbine and implies many men in the regiment also had them.
Has anyone ever been able to identify which of the companies of the 2nd Missouri Light Artillery manned the two 3" ordnance rifles in Cole's column? I have never been able to confirm the existance of this type artillery piece in Cole's column via a primary source, only undocumented secondary source(s). (This information might appear in a quarterly ordnanc report of the regiment.)
Gil