Note the W&C Scott pinfire I mentioned uses a right swinging lever pivoted on a vertical pivot, just as does most any modern top lever gun. The bolt is a sliding bolt in the bar of the frame engaging a single bite in the bbl's underlug, (Not quite as heavy & sturdy, but same principal as a Parker or Win 21). I have never dis-assembled it to see exactly how the connection between lever & bolt is made, but it apparently does "Not" use a vertical spindle, as this was not patented until 1865 by Scott. Mr Crawford estimated build date for mine between 1863-1865.
