As I posted on this site earlier, the guide rod/recoil spring assembly on my G30 broke yesterday. After doing a search here and talking to the Glock customer service rep I thought others might be interested in what I conclued/learned from this experience. On the bottom of the barrel where this assembly contacts the barrel there are two positions where the assembly will contact the barrel. One is a half-moon shaped recess and the other is a horizontal step or shelf type detent. When you disassemble the weapon you will note that the rear of the assembly rests on the horizontal step. This is the correct operating position. IT IS NOT the proper reassembly position. When reassembling after a field strip, place the rear of the guide rod into the half-moon recess. It says this in the owner's manual but I either didn't read the fine print or didn't recall it. I am not sure that this malfunction is not my fault. I may have not seated the guide rod assembly in the proper position. I don't really recall. Since I don't recall it being an important item to check this may well be the problem. Hope this helps others avoid the inconvenience.