Having owned and fired three barrel lengths of this gun I have ample doubt this could happen especially to a Command Sgt Major. Even a desk warrior has had considerable shooting experience - especially a 23 year vet.
Here is another example
http://bearingarms.com/negligent-suicide-with-a-500-smith-wesson-revolver
/http://www.wgem.com/story/23864457/2013/11/03/woman-dead-in-accidental-shooting