Can’t cock Talon SS

Hi all. I took apart the Talon today to put in a new hammer spring. Once reassembled, I wasn’t able to cock the gun. I can get the breach halfway forward, but it wont go any further. I’ve disassembled and reassembled it about 5 times now, but can’t seem to find the issue. I’ve tried using the old spring, but no luck. Ive trying forcing the breech forward, but no luck with that either. There doesn’t seem to be anything blocking the breech from sliding up.
Only modifications are the Talon Tunes brass hammer and TT breech. It’s an older style talon SS, and I’ve removed the safety on it.
Any thoughts on what this might be would be helpful!