Navy SEAL - MK 46 Machine Gun

A Navy SEAL (foreground) armed with a MK 46 Mod 0 light machine gun.

Note the SU-231 holographic sight mounted on the weapon's top rail.

The MK 46 Mod 0 is a variant of the M249 Squad Automatic Weapon (SAW), a 5.56mmx45mm belt-fed machine gun in common use throughout the U.S. military.

The MK 46 Mod 0 is the second in a series of M249 variants that have been designed especially for use by SOCOM special operations forces.

The first of these was the M249 Special Purpose Weapon (SPW).

Designed to be lighter than the M249, the SPW did away with the SAW's carrying handle and vehicle mounting lug.

Pictatinny rails were added for easier mounting of accessories such as optics and laser devices.

The SAW's magazine well was removed, cutting down on weight but losing the ability to use M16/M4 magazines in the weapon.

The SAW's fixed buttstock was replaced with an adjustable version.

The MK46 Mod 0 differs from the SPW in several ways.

It features a 4-sided rail assembly, compared to the 3-sided one found on the SPW.

The MK 46 Mod 0 swapped the SPW's adjustable buttstock with a lightweight fixed version.

The current model in use by SOCOM is the MK46 Mod 1.

This model features an improved bi pod, brings back the carry handle and reverts the heat shield to a standard M249 version with a 3-sided rail assembly.