While Googling something entirely unrelated, I stumbled across this site/blog...
Bulgarian Arms Blog by gunman
http://gunman.biz/
I don't know if this is the same 'gunman' that is a member here, and the main blog is not what interested me...
It's the extensive archive of arms schematics...
Arms Schematics
http://gunman.biz/sheme/
http://gunman.biz/sheme/A-F/
http://gunman.biz/sheme/G-O/
http://gunman.biz/sheme/P-Z/
It doesn't have every gun...But it has a lot of them...