A system includes a back pressure valve configured to mount in a mineral extraction system. The back pressure valve comprises a cylindrical body comprising a venting port coaxial with a longitudinal axis of the cylindrical body and a plunger disposed in the venting port, wherein the plunger comprises a stem that extends from the venting port into an adjacent cavity of the cylindrical body. A method of operating a valve, includes biasing a plunger to an open position, biasing a valve locking mechanism to a locked position in relation to a bore of a mineral extraction system, and biasing a plunger to a closed position.