I found it was quite a pain finding autofire circuit information online (the only website that has any sucks) and so I had to come up with my own design. It works pretty damn well though and since it was something I spent a long time looking for I figured it would be good to share. check it out on the bottom of my webpage (http://www.freewebs.com/segasonicfan/arcadeworks.htm)
If you don't want to wait for all the loading, here's a copy of just the schematic:
(http://i18.photobucket.com/albums/b134/Segasonicfan/555TimerSchem.png)
-Segasonicfan
Syncro AF:
(http://img371.imageshack.us/img371/166/syncgz1.jpg)