I had the same problem with both of my Black Diamonds. You are on the right track for a "cure". I went to the nut/bolt sling stud, recessed the nut so it is a little below flush with the bottom of the barrel channel.

One of mine let go when I was carrying it through the woods slinged during the 2002 elk season. The front sight hit the ground pretty hard, but the pine needles cushioned the impact to the point where it didn't break the front sight. Lucky.