The shorter fluted barrel with muzzle brake is a 30X357 Maximum.
I assume this one is for hunting. I like to ask if you plan or suggest hearing protection when hunting with a brake? I have avoided a brake or porting on any gun I might carry in the field.
I been researching the x frame smiths in 500 mag and read more than one comment about potential, serious, permanent hearing damage from just one time shooting of (perhaps)a bear without hearing protection. All factory 500 mags have brakes. That is a deal breaker for me.