CHAPTER 13
ORGANIC SUPPORT WEAPONS: M203 AND
MACHINE GUNS
This chapter is a continuation of the discussion
about weapons. Here you will learn about support
weapons available to the Seabees. Information on the
40-mm grenade launcher, M203, the M60 machine gun,
the .50-caliber Browning machine gun, and the MK 19,
MOD 3, 40-mm, machine gun is provided.
THE 40-MM GRENADE LAUNCHER,
M203
When equipped with a grenade launcher, the
Ml6A1 rifle becomes the 40-mm grenade launcher,
Figure 13-2.--The 40-mm grenade launcher M203, controls, and
M203, and loses its identity as the M16A1 rifle.
their identifications.
The launcher attachment is assembled by a qualified
armorer only. As a member of a weapons platoon, you
HANDGUARD AND SIGHT
only have the responsibility for the employment,
ASSEMBLY GROUP
trajectory, method of firing, firing effects, malfunctions,
and care and cleaning of the launcher attachment.
The handguard portion of the assembly group is a
molded plastic protective cover that fits over the barrel
The 40-mm grenade launcher, M203, mounted on
of the Ml6A1 rifle. The cover prevents the operator
the M16A1 is shown in figure 13-1. It is a lightweight,
from coming into contact with the barrel when it
compact, breech-loading, pump-action (sliding-barrel),
becomes heated from rapid firing. The heat produced by
single-shot, manually operated weapon.
the rifle barrel dissipates through the cooling holes and
The launcher is approximately 16 inches in overall
slots in the cover. The protruding plastic tab on the left
length; it weighs approximately 3.6 pounds loaded and
side of the cover prevents the barrel latch of the grenade
3 pounds unloaded. Its maximum range is 415 meters,
launcher from being accidentally pressed when the
its area target range is 350 meters, and its point target
weapon is laid on its side.
range is 150 meters. The grenade launcher controls and
The sight leaf portion of the assembly group is a
their identifications, as shown in figure 13-2, are
metallic folding blade sight. It provides range selection
discussed in the sections that follow.
Figure 13-1.--The 40-mm grenade launcher, M203, mounted on the M16Al rifle.
13-1
