Weather or not snake/bird shot loads will function through a semi. auto must vary between guns and ammo.? Because my snake loads function through my .45 Kimber just like any other load.
As far as CCW, I like my Ruger LCR .38 hammerless. It can slip in or out of a pocket with less of a chance of snagging. But, I don't always carry it, sometimes I feel like a nut and carry the .45 auto. IMO, anything is better than a .380 auto.. Is the .38 special enough, depends on many factors, but it'll more than likely stop someone in their tracks.