As a person who owns multiple black-powder firearms, including a few flintlock muskets and rifles, this footage triggers the shit out of me. The fucking magic fox thing I can accept without question, but the mundane flintlock being treated like that bothers me.
The wadding that the musket ball is packed in as it is loaded into the barrel both keeps the powder from escaping, and seats the ball against it through compression. Only during 'rapid' reloading during regimented combat would a soldier drop a naked musket ball down the barrel, then immediately aim, prime the flash pan, and fire. People either hunting, or using pistols would have a patch of linen cloth that would be put over the muzzle, then the ball would be pressed into it before being rammed in. The ball would not roll out thanks to that.