I tried using Valve's prefab but it only let me take one Combine ball out then shut down unless I placed the ball back into it in which case it would spawn another one. Repeating this process resulted in tons of Combine balls that would just float around my level. I have since fixed this multiplier problem by modifying the prefab to spawn one ball after the previous one had blown up. I also was able to prevent the balls from being placed back into the dispenser once it was taken out. When fired back at the dispenser they now just deflect off of it and continue to ricochet off the walls until they detonate, thus respawning another one. I couldn't ask for a better result. If anyone wants this modified prefab, you cand find it later tonight in the prefab section.