Through Ancestry.com, I have been reading the Krag-era annual reports of the Adjutant Generals of the Illinois, New Jersey & Ohio National Guards. I started out trying to learn about the guy who lived next door when I was a kid.  Then I found the Ohio reports & thought maybe I would learn about the purchase of Stevens-Pope barrels.  Nothing so far, but I learned that the Ohio NG had trapdoors & only received their first 800 Krag rifles in 1902.  In 1906-07, the Illinois NG traded their Krags for 03 Springfields before the Ohio NG was completely armed with Krags.  The Ohio Naval Militia was armed with Remington-Lee  and Trapdoor rifles, all 45-70s.  There are tens of thousands of pages to wade through, probably 120 pages per Krag tidbit.  If you are a subscriber to Ancestry.com, check it out.