Mag prime/handle issues

Hi guys, when I disassembled my hk416 the pull trigger / mag prime handle thing fell out and i could never figure out how it goes back in nicely. The main spring would always fall off and the handle would never have enough tension to slide itself back into place after pulling it.
Did I overstretch the spring by accident? Any one have a write up on how to assemble this part?

A lot of m4 based blasters have a problem with that spring. Very easy to overstretch. I ended up replacing with one from bunnings