It was never a "Civil War", an act of Congress (as I rcall was in the 1920s) declared the official name to be "The War Between the States". Since "The WaH" ended in 1865 of course the Win 66 had no part of it, nor did the Volcanic have much impact. The Henry (successor to the Volcanic) & the Spencer were the two repeaters which saw much use during this Late Unpleasantness. At the Batle of Hoover's Gap in middle TN, about 50 miles from where I live was fought the first battle in which an entire Battalion was equipped with repeating rifles. Col Wilder, the Battalion Commander under General Rosecrans who had personally signed for every man in his battalion to purchase their Spencer, took in an afternoon "The Gap" which Rosecrans had hoped they would be able to accomplish in 3 days. My ancestors & relatives who were there were on the receiving end, not the firing end of those Spencers. There are tales from my family from a little further south where some minor fighting took place in an area known as Liberty Gap of some of my ancestors crawling under their bed & listening to the bullets flying around, & through, their house above them. Primary ancestors of mine who lived & some fought, in this area were Elams, Hoovers, Edwards, Millers, Binghams & Fulkses
The 71st Illinois with Henry .44 caliber rimfire rifles. Most Illinois units were equipped with lever actions.

Pete