Making a Burnside Carbine would entertain any master machinist for a long time! I thought they were somewhat awkward, but the troops who used them reported they liked them. I haven't read any first hand accounts, however small "stacks" of fired Burnside cartridges have been found on some battlefields. By stacked I mean like ice cream cones, one inside another forming a stack of several. It's believed once a trooper pulled the first fired case out with the next loaded round, or maybe had an empty handy for the "Tool" and used it to pull others out forming a stack of casings to be dropped when it became too long to easily handle or when the shooting stopped.
The men of both sides loved the Sharps Rifles and Carbines. They were quick to load, no empty case to pick out, accurate, and they packed a punch, even at long range that many other breech loaders lacked. They were popular enough for the Confederacy to produce their own copy, Minus the Lawerance priming mechanism at Richmond Arsenal.