United States
Consolidated B-24 Heavy Bomber
B-24J-155-CO-44-40332
B-24 Waist Guns
Station (Frame) 6.1
Left Waist Gun Assembly, above photo. The late B-24 waist gun comprised of an AN-M2 .50 caliber machine gun attached to a
Type E-13 Gun Mount Adapter, Type K-7 Mount with Type C-19A Mount Adapter and a Type K-13 Compensating Gun Sight.
On the top cover of the AN-M2 is a Type J-4 Gun Heater.
This configuration was only used in late B-24 Liberators that were produced with enclosed waist gun positions.
Right Waist Gun Assembly, above photo.
B-24 Waist Guns in detail:
E-13 Gun Mount Adapter, above left photo.
This is what the E-13 Adapters looked like when they were originally obtained. The E-13 in the rear of the photo was missing
the "duck bill" sight mount, and grips when this photo was taken. This has been corrected.
E-13 Gun Mount Adapter Nomenclature Plate, above right photo.
AN-M2 .50 Caliber Machine Gun, above photo.
The AN-M2 was used in all positions on the B-24 Liberator - the Ball Turret, Nose Turret, Top Turret, Tail Turret and both
Waist Gun Positions.
The two AN-M2s pictured above are compliant with BATFE standards by having a replica 1/2" thick right side plate, prohibiting
the fitting of any internal machine gun parts. The AN-M2 pictured above is shown prior to restoration.
One of the details that differentiates the AN-M2
.50 Caliber Aircraft Machine Gun from the M-2
Ground Machine Gun is the top cover. The top
cover has the added provisions to aid opening
while wearing heavy gloves, as seen on the rear
side and top of the cover.
This photo also shows the thick cuts made during
the demilitarization process. This AN-M2 has not
been fully restored.
K-7 Mount, rear and front, above two photos.
The K-7 Mount supported the entire AN-M2 .50 caliber machine gun to the side of the aircraft.
Note the large springs housed on the inside of the mount. These springs were added to compensate for the weight of the gun
assembly. This afforded the gunner a better ability to handle the weapon and not fight the weight of the weapon when
engaged.
J-4 Gun Heater, left photo.
The Gun Heater was electrically powered and kept the guns warm at high altitudes to avoid freezing when not firing.
C-19A Gun Mount Adapter, right photo. This connected the E-13 Gun Mount Adapter to the K-7 Mount.
K-13 Compensating Gun Sight, left photo.
K-13 Nomenclature Plate, above photo.
The K-13 Compensating Gun Sight was a late war
innovation that used the aircraft altitude and speed
with the direct correlation of where the weapon was
pointed to calculate the reticle. The aircraft altitude
and speed was programmed on the rear of the sight.
The correlation was determined by drive lines that
connected the K-13 Sight to the K-7 Mount.