Watch where the guide rod comes out of the front of the slide. There are slides out where the relief for the spring is countersunk to deep and the slide spring will push out the front of the pistol. The spring will actually break the front out of the slide. If yours has a bulge in it return it to Kel-Tec. Pulling a pistol for defence and shooting a slide spring at them wouldn't be cool. I think you can do a search for peening. This problem doesn't seem to be well known.