This complicated tool is the BGI "three-handled" Berdan decapper and capper. This one is in 45-70. According to Jim Zupan in his very interesting book, Tools, Targets and Troopers, these tools sold for $15 per dozen in 1882 and were part of the 1880 Frankford loading sets. The top handle controls the protrusion of the little "picker" that actually extracts the Berdan primer.
