My bros has a Benelli Nova and the bolt seems to be rusted completely shut. The back of the firing pin just moves with the head of the bolt and it should be able to compress (in order to punch the shell). I have the whole bolt soaking in naphtha oil for the night. I have already taken a lot of PB blaster to it trying to free it up. Any advise on how to break this free?

Sorry if this has been discussed I used the search but only got 2 very unrelated results