According to some embodiments, devices, systems, and methods of connecting and sealing against the introduction of liquids a receiver booster and a detonating cord in an exposed perforating gun are disclosed. According to an aspect, an encapsulated receiver booster is disclosed. The encapsulated receiver booster has an effective connection and seal with a detonating cord and the seal provides consistent integrity against the introduction of liquid, occupies a relatively small amount of space around the connection between the detonating cord and receiver booster, and is configured for use with exposed perforating gun systems. According to other aspects, associated exposed perforating gun systems and methods for connecting and sealing a receiver booster and a detonating cord are generally disclosed.