Figure 2-40.--.50-cal. HB Browning machine gun (M2).
The M2 BMG is only equipped with an air-cooled
heavy barrel (HB) since the light air-cooled barrel is no
The .50-cal. HB M2 Browning machine gun is a
longer in use.
belt-fed, recoil-operated, air-cooled machine gun. The
gun is capable of both semiautomatic fire and automatic
aboard surface ships, but it has since been installed on
most types of ships and landing craft.
Ammunition can be fed from either the left or right
The .50-cal. BMG is a complex weapon, beyond the
side of the receiver (alternate feed) by having some of
scope of this TRAMAN. Therefore, we will not discuss
the gun's parts repositioned. However, under most
its mechanisms and principles of operation. In this
circumstances, the ammunition is fed from the left side.
chapter, we will simply describe the weapon and
A disintegrating metallic link belt is used in feeding. To
discuss how to operate it. For detailed information on
prepare the gun for automatic firing, you must load the
the .50-cal. BMG, refer to the Army's FM 23-65.
first round manually.
The main characteristics of the .50-Cal. BMG (M2)
The force for recoil operation of the weapon is
are as follows:
furnished by the expanding gases and is controlled by
various springs, cams, and levers.
Weight of the receiver
Air cooling of the weapon is permitted through
maximum exposure to the air of the barrel and the
receiver. Perforations in the barrel support allow air to
Weight of the barrel
26 lb (approx)
circulate around the breech end of the barrel and help to
Total weight of the gun,
126 lb (approx)
cool the parts. The heavy barrel is used to retard early
complete, on its tripod
Maximum range (M2
Operating the .50-Cal. BMG
The safest and best way to operate a .50-cal.
M a x i m u m effective
machine gun is to follow the correct procedures. By
following set procedures, you prevent damage to the
Cyclic rate of fire
gun and possible injury to you or others in the area. The
operating procedures of the .50-cal. BMG include
Muzzle velocity (M2
prefire checks, loading and unloading, and postfire
Length of the gun overall
65 in. (approx)
The primary prefire check requirement is the
inspection of the weapon's headspace and timing.
Length of the barrel
This is done with a head-space and timing gauge