[riverrunner]

The Magna Ring was for S@W revolvers. just do a google search and one well find a lot of info

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=10&cad=rja&ved=0CFEQFjAJ&url=http%3A%2F%2Fen.wikipedia.org%2Fwiki%2FPersonalized_gun&ei=IOQJU5H3MYrkyAGC-YDoAQ&usg=AFQjCNHFN9UBPwJJ—c5wtQMckcsGqYRWg&bvm=bv.61725948,d.aWc

[MasterGunner01]

Indeed, Colt also had its own “smart gun” design based on the Colt 2000 9mm pistol. Here: http://www.freerepublic.com/focus/news/791413/posts