I agree with WP'76 but I as a rule of thumb with any fire arm I purchase before putting rounds out of it get it checked fully by my gunsmith I mean I have to pick it up from there so why not have him check it before going and shooting it.
And agree with MTOMS as well it may have been a slam fire as to blow a breech apart would take a gross overload or an obstruction but still scary stuff with the case in any position but in the chamber where it should be before ignition.