The magnet pulls the trigger froward...if it were too strong, the trigger would definately be springing back into place.
Debris in the trigger sounds like a likely culprit. Also, if you tried one of those "washer" mods to get rid of side to side slack, it's probably the cause. That side to side slack is left for a reason.
"There once was a buggy AI
Who decided her subject should die.
When the plot was uncovered,
The subjected discovered
That sadly the cake was a lie."