I just have a quick question, any info would be much appreciated. I bought a new gen 4 g19 a month or so ago and I have around 400 rounds through it. The gun has been great. I had a gen 2 before this and I like the gen 4 a lot better. The only question I have is this- if I lock the slide back and move the rear part of the slide from side to side it makes a popping noise. There does not seem to be excessive play in anything. I know I'm probably being too anal, but I've looked at this forum for a long time and got a lot of good info off of here, so I figured I would register and ask. Thanks in advance for your answers.