XM16E1 converted directly from Metal Gear Solid 3: Snake Eater.

The model and texture are original, both extracted directly from the original game folder. In addition, every effort was made to realistically allocate the weapon in CJ's hands.

As of now, it is technically impossible to extract and convert the original weapon icon for GTA SA.

Original description of the XM16E1 in Metal Gear Solid 3: Snake Eater:

The XM16E1. A state-of-the-art assault rifle currently being field-tested by the U.S. Army. Uses small caliber, high muzzle velocity 5.56 x 45 ammunition. Magazine is 20 rounds. Features several modifications geared toward jungle combat.