You can own a cannon Now! Dixie Gunworks has them for sale all day long. Google them and you’ll see.
Videos of people shooting cannons, some homemade. https://www.youtube.com/results?search_query=shooting+a+cannon
I know several people that own CW era 10 lb. Parrot rifles,
3-inch ordnance rifles and 12 lb. Napoleons. Some of them live shoot with real ammunition at the NSSA matches.