The Madsen light machine gun is note-worthy for several reasons - it was the first military-issue light machine gun developed and it was successful enough to remain in production into the 1950s (long after every WWI-era machine gun was long out of production). It was also one of the most usual machine gun mechanisms ever successfully designed - one of the early "what if we try this?" sorts of mechanisms that actually worked quite well. You probably saw the video of me running a Madsen in a 2-gun match last week, and the reason I actually had the gun on hand was to do a more academic video on its history and function. So if you have always been confused about that the heck is going on inside that mechanism, grab a cup of coffee and let me walk you through it...