I remember reading somwhere that if you get a new bolt for the 2000 Autococker, you'd have to replace the back block. I will be recieving the gun tomarrow through shipping, and along with it a Mako Venturi Bolt. I was just wondering if this problem is existant on the '02 'Cocker, and if it was, how much would a new back block coast, and which one should I get? Thanks a lot for the help.