It's a modern folding stock from IZHMASH, that uses a button to release it when folded and locked.
There is a big hole above that button, and i have no idea why.
The hole is closed with a cirkular door on a spring hinge which pushes the button backwards.
There is a big spring inside the middle of the stock. It does not contact the door. I can't pull it out with my finger, i can barely reach it.
It doesn't even show up on the instruction manual.
Here you can see it, with a shotgun shell in it
Excuse my hairy legs
There is a big hole above that button, and i have no idea why.
The hole is closed with a cirkular door on a spring hinge which pushes the button backwards.
There is a big spring inside the middle of the stock. It does not contact the door. I can't pull it out with my finger, i can barely reach it.
It doesn't even show up on the instruction manual.
Here you can see it, with a shotgun shell in it
Excuse my hairy legs