New to S & W. The Shield is my first. Have Glocks but bought the Shield because I wanted 9mm single stack. Bought two weeks ago. Cleaned and taken to the range for 60 rounds with wwb, Hornady. No problems that I notice. Just got back form range yesterday with 100 rounds down range. When cleaning the barrell I noticed on the outside of the barrell at the end was a crease around the barrell tan is uniform aroud it. It starts around the last 1/4 inch of the end of barrell. When you run your finger over it that last 1/4 inch is higher than the rest of the barrell but is uniform around the barrell. Is this they way they are cast or defective? Looking at the end of the barrell the inter ring where the rifleing starts is pitted and is not round. there is an outer ring (looks like an inter and outer barrell) that is smooth. My glocks do not look this way. If you have a shield let me know if it is normal or do I have an issue with this barrell. The gun shot fine expect for a few times slide would not lock back last shot ( Imay have had thumb on slide or weak load) and it is real hard to load a mag full. Have to grad the slide and squeeze hard to get the mag to click. Thanks for the help. I want to love this gun!