Doug White used a 44 Mag at extremely close range when a Grizzly attacked him after he shot & gutted a Moose.
Check out the story & pics.
https://thegreatwhitehunter.wordpress.com/the-longest-minute-terrifying-bear-attack/
Wow.
Talk about a lucky shot under pressure!
I'm sure that if given the choice neither man would choose a .44, formidable though it is.
I'd be hauling around a shotgun loaded with slugs.