SS always drops machinegun replacement

The SS always drops the actor that replaces the machinegun and doesn't drop a clip (or an actor that replaces the clip) during all subsequent kills with the machinegun replacement in the player's inventory.

Although it's an easy fix on the modder's end, it would be inconvenient for the modder to replace the SS actor with one that has a specified item drop that correlates to the machinegun replacement actor.