An injector system includes a syringe and an injector. The syringe includes a body portion and a plunger movably disposed within the body portion. The injector includes a housing defining a front opening therein, a drive member extendible through the front opening of the housing for imparting motive force to the plunger disposed within the syringe, and a pressure jacket assembly associated with the housing for substantially enclosing the syringe during an injection procedure. The pressure jacket assembly includes a jacket cylinder having an open front end for receiving the syringe and a front member associated with the housing. The front member is pivotable between a closed position for retaining the syringe within the jacket cylinder and an open position for allowing the syringe to be inserted into and removed from the front end of the jacket cylinder.