Once upon a time, a long time ago, my cousin came to camp from Erie PA. He was 12 years old and was going to hunt with his dad's Winchester 30-30 rifle.
Now I don't know all the particulars, but I would bet that he was dry firing the gun and the firing pin broke.
When they took it to the rifle range to sight it in, it would not shoot.
I don't remember for sure - because it was 28 years ago, but i think that my dad might have took it apart and found that the firing pin was broke.
Murphy's law says that anything bad that can happen, will - and at the most inopportune time. Sunday afternoon before deer season.
Well I had been in some situations before and I made friends with a local gunsmith that was retired. At that time, he was in his 80's and lived with his wife on the edge of town.
When I knocked on his door, he welcomed me in.
In his possession was a bunch of old derelict guns, some of which I am sure were Mossberg .22 rifles.
When I showed him our situation, he took the gun apart and found the broken part. He said - well I would like to help you, but to fix your problem, I would need to be able to silver solder the new pin in the old assembly and I am out of Mapp gas.
Well the grandfather of the boy with the broken rifle was a Appliance Repairman and in the back of his van - low and behold was a complete welding torch assembly - with Mapp Gas.
The Gunsmith was a good machinist and he ground the old firing pin down to the larger part and then he put the larger part in a lathe and he drilled a hole the same size as the firing pin through the broken piece.
He then took a drill bit and fit it inside of the old piece and silver soldered it in. Then he ground it down until it was the proper length and test fired it with several dummy rounds.
When he got the depth set properly - the gun was fixed - probably better then new.
He refused to take any money, even though he worked on that rifle for a couple of hours and used his own tools and his own drill bits and his own silver solder..
So the moral of this story is - although the gun is broke - sometimes the cost to fix it will be more then what it is worth, unless you can find someone to fix it for you that is willing to repair it at a reduced rate.
The last machine shop I worked for charged $65 a hour!
Your picture is blurry, but if I see what I think I see - the gun is junk and you should throw it away.
It looks to me as if there was a crack developing on the side of the body of the bolt. Just below your thumb nail on the opposite side of the bolt.
I can't diagnose your rifles problems over the internet - but I'm not sure that the hammer part that is above the firing pin is supposted to be in contact with the firing pin until after the striker is dropped..
If it was a Steven's - you could turn the knob on the end of the bolt and the striker would touch the firing pin.
Here is a link for replacement parts..