I got a PWS off GB about a month ago, and it was sold as new, never fired.  So I cleaned the bore and when I went to the range, it wouldn't cycle.  When I took it apart I found the small piston to be missin.  It was obviously not fired, and it didn't look as if it were ever apart.  I still contacted the seller to see if he might have lost it and stated he never disassembled.  So I contacted PWS (given the story and who knows who could be lying I was worried).  They mailed me a new one and all is well.  I posted now as the other post on a PWS problem sounds like mine.  Stuff happens and it's a nice rifle.