I believe that you still have to acquire the recipe for .44 SWC from Jules to make it, whether you take Hand Loader or not (possibly a bug).
Yeah, if it's not a bug they need to rewrite the description for the hand loader perk. Also, you'll need a 60 in survival to get the recipe from Jules (and pass a gun skill check too).
At any rate, used with the cowboy perk it's definitely worth the trouble to load SWC ammo (assuming lever guns work in your game).