A few things to check, first, your nozzle return spring looks damaged, it should not have a coil dangling at the end. It should fit perfectly in its slot on the blowback chamber.
Second, on one of the pic (linked below this paragraph), it looks like the nozzle is maybe catching on the internals. It's hard to see, but if it does catch, then is means your blowback chamber is misaligned and is pointing downwards, which causes exactly the problem you are having. Make sure you screw the screw behind the chamber (where the hammer hits) first, then make sure that the chamber is not moving when you screw the top screw. If your nozzle chamber spring was misaligned and was partly crushed between the slide and the chamber it can cause this problem. That would explain the damaged nozzle spring.
[Edit] Wow, opened that tab a few hours ago, now just replied and there's a bunch of replies... looks like you already found the problem.