Marathon Symbol on AR in Halo 3

On Halo 3, (it may be in other games, I only saw it in Halo 3 though) get an AR, and start a game. Go to theater and detach the camera from your character. After that, move to the side of the gun, and zoom in near the shoulder to see the Marathon symbol on the stock near the top (at first I thought that it was on my Recon shoulder, you know, the thing that sticks out? Then I zoomed out and saw it on my AR).