On another occasion a week or so later, John (I think) and I were working in an area far to the west of Dong Tam where there were expansive open areas of high grass growing. The days scouting in this area quickly became boring in that it did not appear that anyone had been in the area for a long time and we were primarily skirting the top of the grass using our rotor wash to scout down into it. There was a fairly brisk breeze that day and on several occasions as I as was hovering with my tail at times into the wind, I sensed poor response in the aft cyclic position but figured I was just experiencing wind gust and continuing scouting. I suppose about thirty more minutes passed as we continued to dart here and there, twisting and turning, when all at once I found myself again with my tail into the wind but now I was in an increasing nose down attitude with a frozen cyclic with only some 15 feet of altitude to the ground. Luckily in desperately trying to extradite myself from my predicament, I unconsciously pushed enough right pedal to turn the nose back into the wind and land the dang thing before it crashed. My chief did some immediate open-heart surgery on the floor board and under seat area within our bird and diagnosed that our problem was the presence of about one thousand empty M-60 shell casings jamming our cyclic controls. He cleaned the mess out and every thing was fine after that. I wrote up our problem and findings in the ships log and to my surprise a year or so later while I was recuperating at Walter Reed Army Hospital, I saw a technical PM article in some helicopter publication circulating the ward that went into detail as to how to field rectify the LOH to prevent expended loose brass from entering into the very area we had reported a YEAR earlier.