It happens all the time in movies, and it often looks easy. Modern homesteader Wranglerstar decided to try to cut a chain with an axe for himself.
After a little trial and error, he continues to make progress. The trick it so do it on a hard enough surface so the chain absorbs the force. It also helps to be really good at placing an axe strike accurately in the center of one link.
• Will An AXE Split A Chain In Half??? (YouTube / Wranglerstar)