.22 blanks vs primed hulls?

[RutCrazed]

I want to start training with a shotgun instead of a blank pistol and was wondering which is louder/more realistic, a shotgun with a .22 conversion shell with ramset blanks or a primed shotgun hull? My .209 blank pistol seems pretty loud on its own, but my .22 dummy launcher seems very loud. I am not sure if being inside a shotgun barrel will down the sound out of either??

Thanks