The firing pin block is designed to prevent the gun from discharging when dropped. If you have ever dropped your gun and it didn't go off, you have no way of knowing if the FP block had anything to do with it.
my step father has a 1991 series 80 government stainless...I bought one at the same time and they were close enough on serial number to be made same day...I sold mine within a month cause I couldn't hit with it...He still has his but never shoots it. As far as I know the only thing that has been in the barrel is cotton. probably safe when dropped...but he does not drop his either.