Not long after I got my M&P 9MM Pro the front sight came loose. I think there was a problem with the tolerances as the sight would just slide back and forth in the dovetail. I took it to a gunsmith as I had a match later than day. He used blue Locktite and I was back in business. In the year since then it has come loose again and again it was Locktited and the fiber rod has broken 4 or 5 times and I have had to keep replacing it. Why does the rod keep breaking? I use a small soldering iron and round the ends. Should the front sight be held in only by Locktite?