It's one of the symptoms of dropping the slide on an empty chamber.
Unless you are a qualified gunsmith do not mess around with the sear/hammer engagement surfaces as you will most likely end up with a 20 pound trigger pull or machinepistol(seen it happen) and that's just not cool.
...
A few years ago I was shown a gun that a shooter had worked on with a Dremel tool . It went FA on him with a full 10 round mag. The last one went into his jaw.



























