JR, I just recently purchased a LW 5.15 for my G20. Until I installed it, I've have virtually no issue with failure to feed or fire with the stock barrel. Since installing it I've run into some of both. More so the failure to fire. What's happening is the slide seems to fully engage but the round doesn't fire. I've checked that the rounds heads are below flush of the barrels lip and they all seem to be. Now I will mention that the rounds are reloads but I don't see anything obviously awry. Also, the primer seems to be hit enough but I'm not certain. A second chambering and attempt to fire always seems to work. Is it okay for me to work the chamber a bit with a fine emery cloth to try and smooth things out? I hardly ever get a full magazine to run successfully. Other mods are the 22lb spring with the steel guide rod, and the 3.5 connector. Thanks.