Crosman optimus stock

Last night I tried to modify the trigger on my crosman optimus. After fooling with it for a while I gave up with it and put the gun back together. I then found that the gun cocks and shoots fine without the stock. After putting the stock on I found that the gun won't cock even though I can pull the barrel all the way down.
 
What did you do to modify the trigger? The sear isnt engaging to hold the piston back from the sound of it, depending on what you did you can either reverse the mod or if you just adjusted the trigger pull you can adjust it back a bit until everything locks up correctly. As for why it is only when the stock is on im not sure, im not familiar with the optimus but im pretty sure it is identical to the phantom which i am familiar with. Does any part of the trigger mech screw to the stock?
 
I would disassemble the rifle and check that nothing in the trigger group is binding up (especially the sear) are you 100% sure that the trigger spring is in the correct place? It could be possible that the trigger spring is out of place and when put back in the stock is binding up. Not sure, but if the trigger is the only thing you removed and nothing is broken that is most likely where the issue lies.
 
Last night I tried to switch the one spring around to the other side like yours is. It must have not been the right place because when I shut the barrel the spring went flying across the room haha. I can't find it because it landed in carpet. I figure I'll just give up on trying to fix it and strip it for parts to fix other guns. Thanks for the help man I appreciate it a lot.