The was done using Issac Hanna-Fords glorious artwork used for Halo Reach.
I used it to make several variations of the iconic Halo Battle Rifle.
The first Row (going down):
The original Design (not Mine)
Long Barrel Version with long Grip for easier control. Used for Long to Mid range marksmen shooting
An odd mix of several guns from halo. I guess its my remake of the MA-23
The second row:
BR-55 with Iron sights and laser pointer
Br-55 with Red-Dot Scope aperture and laser pointer
Br-55 With Red-Dot sight, Silencer, and laser pointer
Remake of the Halo Reach DMR
Long Barreled version of the DMR
LB DMR with Red-Dot sight, Silencer, and Grenade Launcher
Well there you have it. I really hope that with Halo 4 on the way, 343 Industries will include weapon customization in the game as I have illustrated here