Hello Tucker and Mudhen. Yes, I know it's been a while since you've seen me. I'm still the old wallhanger54 but since I changed ISPs and couldn't remember my password I had to start from scratch again with a new name. Hope to see you around the forum. As for yet another answer to this fellas question about the Nova. Try shooting the same ammo without the extension. If it does not stick then there may be a solution. Sometimes, the actual extended tube that screws into the connector which screws onto the magazine tube is too long. The way to check...with the mag extension on the gun and tight, unscrew only the extended part of the tube 1 or 2 turns from the connector. If you can then tighten the connector a few clicks then you will have found your problem. What is happening is that the barrel is not firmly seated and is not allowing the chamber to fully support the shell allowing the shell to expand. Two ways to fix it....1. Take out the mag spring , put the barrel on with the extension and the connector tight to the barrel and the extended part of the tube loose so you know the barrel is seated properly. Remove the tube extension, put some red Loctite on the threads (not too much) and screw it back in until it is snug finger tight, not torqued. 2. You can also remove the extended part of the tube and file some metal from the part that meets the factory tube, but just enough so that it completely screws in flush without binding. You dont want a big gap inside your magazine for the follower to get stuck on. That being said, polishing the chamber isn't a bad idea either, it keeps them from being finicky. Hope this helps.