There is no glitch.
U can't! :(
The only way to get all the armor is by completeing the achivement or task online to get that sertain permutation.
http://hubpages.com/hub/Halo-3-Armor
go to http://hubpages.com/hub/Halo-3-Armor
you get all the vidmaster achievements on halo 3 and halo 3 odst
No, there is not.
No.
All the armor are the same it's just the way how you want to look WRONG! the best armor in halo 3 is the recon armor and you have to be a member of bungie OR get all 7 vidmasters in halo 3 ODST
By getting skulls.
get all skulls
There is no cheats.
To get security armor in Halo 3... all you have to do is get all of the original 49 achievements (you don't need the new mythic or legendary achievements).