An interrupter module for a molded case circuit breaker has a floating antifriction disc between the module casings and the blade carrier which overlays the blade carrier with rim walls of the disc. The rim walls are located at segments of the disc containing the drive pins of the module. If gases from circuit interruption expand the interrupter module sides and force the disc away from the blade carrier, the rim walls remain over the blade carrier and protect the drive pins from contaminants carried by the gases.