I have heard that the trigger springs on the WE series PX4 are terribly feeble and I now learned for myself that they are. I have looked online and couldn't find a factory replacement, but I did find one solution. As it turns out, you can modify a real steel PX4 trigger spring to fit. I ordered one and I am going to try and fix mine. I will be posting a follow up as to whether it works or not shortly, hopefully by the end of this week.