I've had a G2 for almost a year. It does great with my 7mm TCU Barrel and a borrowed .44 Mag barrel. I just bought a .357 Mag barrel on ebay with which I'm having a problem. The barrel appears to be in excellent condition. It fits on the gun fine and closes securely. The ejector and locking mechanism don't appear to be worn at all. However, the trigger won't pull back to the cocked position with the barrel on the frame. Any idea what the problem is? How do I fix it? I checked the other barrels after trying the .357 Mag and they work fine. Any advice would be appreciated.