I got a striker-fired semi-automatic vz58 rifle recently and, as per usual, the first thing I did was strip it, clean it, and reassemble it.

But of course I forgot to put the striker in, so when I function tested it I mashed up the striker spring (think long coil spring with no guide rod inside it) and seized the action. Eventually with some (reluctant) use of force I popped it open and freed up the jammed spring.

Got a new spring and all is good now.

I understand your pain.

Lesson is, when playing with a firearm for the first time, don't get sloppy and put it back together hastily while home for a quick lunch break from work. Double check each step so you don't forget something or put a part in backwards by mistake.