need help.. breech wont lock

[Lunar]

Here are some more pics.

The magazine spring should be very strong. If you are able to push the magazine button all the way down without problems, that is probably your problem: Magazine spring that is too weak.

No! I cant push the button all the way down. I can push it maybe 1/4 of all the way. The magazine spring is very strong at me too.

Unfortunately I haven't access to antoher magazine.

But I think my spring of the magazine is not weak.

Maybe the holdopen is jammed?

So please tell me what a Lugar I have.