The M1911 S-TAC was only available to DICE Devs. The only way to get kills with it was to be a DICE Dev or pick up their kits.

If you have one or more kills with the M1911 S-TAC then you can apply to this club.

This platoon is only available to those who managed to get a kill with the s-tac before it was available to the public, if you were one of the few lucky ones that got a kill and would like to join this platoon you must show proof that it was before the weapon became available to the general market.

PS3 M1911 S-TAC Leaderboard : March 4th, 2013
http://i.imgur.com/dxHaJTt.png

http://www.youtube.com/watch?v=SXk2AZOKt1A