Pull firing pin and clean out any dirt or oil in there.
Maybe replace the hammer spring.
Have you tried any other ammo?
Could be a batch of hard primers
This appears to be done after it left the factory (PC). IMHO
The sights are nothing the PC used and the factory would mark any TDA model that they converted to SA.
The blue controls are also a later thing.
The 104401 " Special" product code was used on several of the early 40 models before the...
That is the .40 Tactical
One of the early 4006 "Special" PC models
One of 200 in the '91-92 time frame
Most had #104401 product codes
There are a lot of inaccuracies in the SCSW PC section
Late 2008 production on Chads. Did the case have a S&W label stuck to it? Any paperwork inside ? Could easily be an interum case. A dealer selling a used gun would have no idea, the same as we don't.