If It HAS to be one of those, the .44 Bulldog. BUT, for MY bug out bag, I'd most likely choose a 7 or 8 shot revolver in .357 Magnum. I like .357 (You regulars here wouldn't know that, cause I've NEVER said it before....

I mean, It's not like I carry one in my pocket or anything, right?) because, as mentioned above, you can shoot .38 Special OR .357 mag. Versatility of ammo. If I were to choose a .44, it would be a .44 Mag for the same reason; it can shoot .44 Special or .44 Mag. I'd put a .357 over a .44 in my bag, because It has plenty of punch, and I've never seen a .44 mag revolver that holds more than six shots, so you can get an extra round or two with a medium or large framed .357, which could come in handy in a bug out.