My 32-40 Stevens that once shot so good started not shooting so good. I suspected a broken firing pin and I was right.  I got a new pin and installed it today.
Everything was great and shooting good until I made a wee bit of a mistake. 
I was breach seating bullets and mistakenly put the breach seating case without a primed back in the chamber and attempted to fire the rifle.   The lack of a primer in that case allowed the firing pin to travel far enough forward that it is now stuck forward so I can not open the breach.
I also can not remove the barrel because the extractor is in the way because again I can not open the breach.
I am afraid I may have to sacrifice the new firing pin to get the breach open.  Anyone got a better idea ?

I have been trying that but its not working.  Its a new pin as of today and was a tight fit.  In the full forward position it would not fall back freely when the muzzle was raised.  It had to be pushed back from the breach face with a flat punch. I had to turn it a bit to get it to fit at all.  I quit with a tight fit thinking that it would work itself in with some shooting.  This has got me stumped and I see only one way out and its not a good way.

I'd consider making a small brass rod to fit into a good one piece cleaning rod and turn the small rod down to a tip that's small enough to fit into the flash hole of your .32-40 case. Then run the cleaning rod with the reduced tip into the case and gently tap it to move the firing pin back. May take some finessing to get the tip into the flash hole, but once in it should move the firing pin back.
After getting it free, I'd consider removing the firing pin and dressing down the tip to ensure it wont be such a tight fit that it could stick again.

I had the same problem and solved it by bumping the stock on the ground. Because of your post I now have another way to solve the problem. Thanks,  Pete