Yeah, you cant just unscrew the hammer, you need to take the whole lock off, because as you suspect there are springs behind it. It should just be something like two screws on the other side and the lock will pull out easily.
Getting the hammer out is a bit tougher, there are a couple springs and they can be a bit tricky. I would take clear pictures of how it all fits on the other side then work slowly and carefully to remove the springs first
Although I gotta say I'm not real sure on the whole bending the hammer idea, I would wait for some more knowledgeable replies on that. It may be unnecessary to disassemble the lock.
I sort of suspect that the lock/barrel aren't fitted properly and that might be the first issue to address.