The headset lock ring is being tightened quite firmly using the proper headset wrenches and I have checked to make sure that the lock ring isn't bottoming out due to too long of a steerer. This one has baffled me a bit as I have owned several older bikes with threaded headsets and not had nearly this much of a problem keeping the headsets tight. This one will stay properly adjusted indefinitely on smooth roads but just a couple of rides on washboard gravel or other rough surfaces and it loosens right up. I'll try the regular Lock Tite as long as there is no reasons not to. The only thing I can think of is that the threads on the lockring are just slightly loose on the steerer allowing enough friction for normal road use but not enough to withstand hard vibration.
Thanks for the response.