I got a KKM barrel as recommended by SWR. They shipped the barrel to me and I proceeded to make sure it shoots fine. It ran with whatever I put through it. Winchester white box, S&B 115 grain, 124 grain Dynamit Noble, Special K subsonic and my reloads which are a duplicate of what Dr. Dater of Gemtech uses (also very similar to Special K). I put the can on and it won't cycle with my reloads or with the Special K. It didn't cycle with the 124 grain Dynamit Noble at first either. I put about 300 rounds of S&B through it WITHOUT the can attached and now it cycles with the 124 Grain Dynamit Noble. It still will not cycle with my reloads or the Special K. Talked to Joe at SWR and he was saying that I have an unusually tight barrel and that I can send it back with my gun and he will get it running. I've decided to mess with it myself first. I put some lapping compound on the barrel and it is smoother now but still won't cycle the 147 grain Special K. Thinking about going to a weaker recoil spring but didn't want to do this. Just wondering what others are using in their SWR equipped Glocks. Are you guys using the factory recoil spring or a weaker one?