NAVEDTRA 43904-C
SEABEE
COMBAT
WARFARE
COMMON CORE
Unit 108
Weapons Fundamentals
Weapons Fundamental
Reference
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(a) NAVEDTRA 14234, Seabee Combat Handbook, Vol 1
(b) NAVEDTRA 14324, Gunner’s Mate
(c) Seabee Battle Skills Guide, Vol 1
(d) NTRP 3-07.2.2
(e) Construction Battle Skills Guide, Book 1, All Hands 2005
(f) TM-SW215-BC-MMO-010, Operator’s and Maintenance Manual for
AN/PVS-12A, Night Vision, Crew Served Weps
• (g) FM 3-22.09, M16A1 and M16A2 Rifle Marksmanship
(h) TM-SW215-B4-MMO-010, Operator’s and Maintenance Manual for
AN/PVS-12A, Night Vision, Individual Weapon
• (i) Construction Battle Skills Guide, Book 4, Crew/Team Skills 2005
Edition
(j) TM 9-1010-230-10, Operators Manual Machine Gun, 40mm, MK19,
MOD3
(k) TM 9-1005-213-10, Operators Manual Machine Gun, Cal. 50,
Browning M2, Heavy Barrel Ch. 1, sec II pg 1-5
(l) FM 3-22.68
(m) MCWP 3-15.1 Machine Guns and Machine Gunnery
4 RULES OF WEAPONS
SAFETY
• PQS Question 108.1 State the four rules of
weapons safety.
• Reference: (c, Ch 1)
Seabee Battle Skills Guide, Vol. 1
4 RULES OF WEAPONS
SAFETY
• Rule 1 – Treat every weapon as if it were
loaded.
• Rule 2 – Never point a weapon at anything
you do not intend to shoot.
• Rule 3 – keep finger straight and off the
trigger until you are ready to fire.
• Rule 4 – Keep weapon on SAFE until you
intend to fire.
WEAPON CONDITIONS
• PQS Question 108.2 State the four weapon
conditions
• Reference: (c, Ch 1)
Seabee Battle Skills Guide, Vol. 1
WEAPON CONDITIONS
• Condition one
– Magazine is inserted, a round must be chambered, and the
safety is on.
• Condition two
– Magazine is inserted, a round is chambered, the weapons action
is closed, and the hammer is forward. This condition applies to
weapons with external hammers except for the M9 service pistol.
• Condition three
– Magazine is inserted, chamber is empty, the action is closed and
safety is on.
• Condition four
– All ammo is removed, chamber is empty, the action is closed
and the safety is on.
NCF Weapons System
• PQS Question 108.3 What weapons systems are
in the NCF?
• Reference: [ref: l, ch. 3, ref: b, ch. 3]
NCF Weapons System
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M9
M16
M240B
50 Cal
MK 19
AT4
M-203
M-500 Shotgun
Define the following
terms
• PQS Question 108.4 Define the following terms
associated with the M16A3 and the M9.
• Reference: (a, ch. 3)
NAVEDTRA 14234, Seabee Combat Handbook, Vol 1
Malfunction & Misfire
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Malfunction
– The failure of a weapon to function satisfactorily, usually because of excess
friction caused by dirt, improper lubrication or carbon buildup.
– Immediate action- you must stop and clean the weapon to correct this problem
Misfire
– A complete failure to fire, NOT a delay in firing that may be caused by a faulty
firing mechanism or a faulty element in the propelling charge explosive train.
– Immediate action
• Strike the forward assist to be sure the extractor has engaged a round
• Tap upward on the magazine to ensure it is fully seated.
• Pull the charging handle to the rear.
• If round is ejected, release handle, strike forward assist and attempt to fire.
• If round is not ejected, check for a round in the chamber, if it is clear,
release handle, strike forward assist and attempt to fire.
• If a round is stuck in the chamber it must be removed before attempting to
reload/ re-chamber.
Stoppage
Stoppage
• Any interruption in the cycle of functioning caused by faulty
action of the weapon or ammunition.
• Immediate action
• Strike the forward assist to be sure the extractor has engaged a
round.
• Tap upward on the magazine to ensure it is fully seated.
• Pull the charging handle to the rear.
• If round is ejected, release handle, strike forward assist and
attempt to fire.
• If round is not ejected, check for round in the chamber, if it is
clear, released handle, strike forward assist and attempt to fire.
• If a round is stuck in the chamber it must be removed before
attempting to reload/re-chamber.
Firing Cycle
• PQS Question 108.5 State the eight operation in a
firing cycle.
Reference: [b, ch. 3]
NAVEDTRA 14324, Gunner’s Mate
Firing Cycle
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Feeding: the feeding action places a round in the receiver just to the rear of
the chamber.
Chambering: takes place as the moving bolt strips the round and forces it into
the chamber.
Locking: holds the bolt in the forward position for a short period of time to
prevent the loss of gas pressure.
Firing: the firing pin actually strikes the primer of the cartridge
Unlocking: after the round is fired, the bolt unlocks and moves rearward.
Extracting: the process of pulling the empty case back out of the chamber. As
the bolt moves rearward extraction occurs.
Ejecting: as the casing is extracted, ejection occurs as it is thrown out of the
weapon.
Cocking: the retraction of the firing mechanism against spring pressure so that
there will be sufficient energy to fire the next cartridge.
Semi/Auto operations
• PQS Question 108.6 Explain the differences
between semi-automatic and automatic
operations
Reference: [a, ch. 3]
NAVEDTRA 14234, Seabee Combat Handbook,
Vol 1
Differences SEMI/AUTO
• A semiautomatic weapon unlocks, extracts,
ejects, cocks and reloads automatically. The
trigger must be pulled each time to fire a round.
• An automatic weapon unlocks, extracts, ejects,
cocks and reloads automatically. An automatic
weapon will fire as long as the trigger is pulled
and rounds are available to fire.
Terminology
• PQS Question 108.7 Define the following terms
[ref a]
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Trajectory [ch. 3]
Breech [app. L]
Bore [ch. 3]
Chamber [app l]
Muzzle [app l]
Muzzle Velocity [app l]
Maximum Range [ref b, ch. 3]
Maximum Effective Range [ref b, ch. 3]
Terminology
• Trajectory: The flight path the bullet takes from the weapon to the
target.
• Breech: The rear end of the barrel.
• Bore: The actual hole in the barrel. It may be rifled or not.
• Chamber: The enlarged part of the bore at the breech that holds the
cartridge.
• Muzzle: The front or forward end of the barrel.
• Muzzle velocity: The speed at which the bullet travels when it leaves
the muzzle.
• Maximum range: The greatest distance a round will travel
• Maximum effective range: The greatest distance at which a weapon
may be expected to fire accurately to inflict damage or casualty.
Ammunition Color
Codes
• PQS Question 108.8 Discuss small arms
ammunition color codes and state the purpose of
each:
Orange or red [ref a, ch. 3]
Violet [ref a, ch. 3]
Black [ref a, ch. 13]
Aluminum [ref a, ch. 13]
Green [ref a, ch. 3]
Reference: NAVEDTRA 14234, Seabee Combat
Handbook, Vol 1.
Ammo Color Codes
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Orange or red: Tracer rounds
Violet: Blank rounds
Black: Armor piercing
Aluminum: Armor piercing, incendiary.
Green: Standard ball ammunition
Maximum Ranges
• PQS Question 108.9 State the maximum range, maximum
effective range, employment, rates of fire, and types of
ammunition of the following weapons: [ref i]
M9 Service Pistol
M1-16A3 rifle
Reference: (i) Construction Battle Skills Guide, Book 4
Describe the 9mm
•
9mm pistol
– semi-automatic
– Magazine fed
– Recoil operated
– Double action or single action firing pistol
– Current issue sidearm
– Capabilities/Characteristics
– Length: 8.54in
– Weight: 2.12lbs
– Weight fully loaded (15rnd mag): 2.54lbs
– Magazine capacity: 15 rounds
– Muzzle velocity: 1230/fps
– Max effective range: 50m
– Ammunition: fires 9mm Ball ammunition
– Safety Features
• The M9 pistol has only ONE safety.
• It has THREE SAFETY FEATURES.
– Ambidextrous safety: Allows for safe operation of the pistol by right and left handed users. Lowers the
hammer safely without causing an accidental discharge
– Firing Pin Block: Prevents any motion of the firing pin and is only overcome by pulling the trigger
– Half Cock Notch: Prevents accidental discharge. If the cocked hammer should fall forward due to a
mechanical failure, this would catch on the sear before the hammer would strike the firing pin.
Describe the M-16A3
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M-16 rifle
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Lightweight
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Gas operated
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Air cooled
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Magazine fed
–
Shoulder fired
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Semi-automatic or fully automatic
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Modes of fire
• Semiautomatic Fire Mode: When a single shot is fired the trigger must be pulled each time.
• Automatic Fire mode: Rifle will continue to fire as long as the trigger is held back
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Selector Level
• Safe Position: Rifle will not fire
• Semi position: The trigger must be pulled each shot
• Auto: Rifle will continue to fire as long as the trigger is held back
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Capabilities/Characteristics
• Length w/flash suppressor: 39in
• Length of barrel w/flash suppressor: 21in
• Weight: 7.8lbs
• Weight fully loaded (30 round ma): 8.79lbs
• Magazine capacity: 20/30 rounds
• Muzzle velocity: 3100/fps
• Max range: 3534m
• Max effective range: Point Target 550 and Area Target 800m
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Rates of Fire
• Sustained: 12 to 15 rounds per minute
• Rapid: 150 to 200 rounds per minute
• Cyclic: 700 to 800 rounds per minute
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Ammunition
• 5.56 Ball: Standard round
• 5.56 Tracer: Used to mark targets or cause incendiary effects
• 5.56 Blank: Training round
• 5.56 Dummy: Totally inert training
Loading/Unloading
• PQS Question 108.10 Discuss
loading/unloading procedures for the following
weapons:
M9 Service Pistol [ref b, ch. 3]
M-16A3 rifle [ref a, ch. 3]
• Reference: (a) NAVEDTRA 14234
(b) NAVEDTRA 14324
Proper
Loading/Unloading
• 9mm pistol./ M-16 rifle
– Keep safety in “safe” position until ready to fire.
– Keep muzzle down range and clear of all troops
– Before loading, make sure bore, chamber, and ammunition are
clean and dry.
– Hold the pistol at the raised pistol position, or place the rifle butt
against the thigh
– Then, remove the magazine by pressing the magazine catch or
release button.
– To make absolutely certain the chamber is empty, pull back the
slide or bolt and inspect the chamber and verify visually. If it is
dark, feel to check. Opening the slide or bolt will eject any round
that may have been in the chamber.
TYPES OF GRENADES
• PQS Question 108.11 Describe and discuss the
six types of grenades: [ref. a, ch. 12].
• Reference: (a, Ch 12) NAVEDTRA 14234,
Seabee Combat Handbook, Volume 1
Grenades
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Fragmentation
– Grenades designed to inflict personnel casualties and damage to light equipment by
projecting high velocity fragments from the detonated grenade case
– The effective casualty-producing radius is about 15 meters
Illumination
– Used to illuminate terrain in night time operations
– Once pin is pulled, GRENADE MUST BE THROWN!
– Grenades used mainly to light up the terrain.
– The MK 1 is the only illuminating grenade currently available.
– It provides about 55,000 candlepower for a period of 25 seconds.
Chemical
– Used for incendiary, screening, signaling, training, and riot control purposes
– Grenades that are chemical filled munitions designed to be thrown by the individual or
projected from the service rifle using a special adapter.
– ABC-M25A2, riot control hand grenade is the most commonly used.
• Filled with a type of tear gas chemical that causes irritation and watering eyes.
Grenades
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Incendiary
– AN-M14 incendiary Thermite grenade is used to ignite combustible materials and to
destroy all types of equipment.
– This TH grenade is cylindrical in shape and weights 32 ounces.
– Contains filler of 26.5 ounces of Thermite mixture
– It uses an igniting delay fuse that sets fire to the Thermite
– The Thermite burns at a temperature of about 4,300 deg F
Smoke
– Grenades that are cylindrical in shape and weigh about 27 ounces.
– They can be thrown about 40 yards with an effective casualty radius of nearly 30 yards
Practice/training
– Used to train personnel in the care, handling, and use of grenades prior to using actual
service grenades.
– These grenades are used for training personnel in the care, handling, and use of hand
grenades before using service grenades.
– Practice grenades simulate the functioning of service grenades to provide realism in
training.
Hand Grenade Safety
Procedures
• PQS Question 108.12 Discuss hand
grenade safety procedures. [ref. a, ch. 12]
• Reference: (a, Ch 12) NAVEDTRA 14234,
Seabee Combat Handbook, Volume 1
Hand Grenade Safety
Procedures
• All personnel handling casualty producing
grenades must wear proper protection
• Never attempt to defuse hand grenades
• Do not remove the safety pin until ready to
throw
• Do not attach grenades to clothing or
equipment.
CLAYMORE
• PQS Question 108.13 Discuss the placement, arming,
safety requirements, coverage, and methods of firing
the Claymore mine. [ref. a, ch. 12]
• Reference: (a, ch. 12) NAVEDTRA 14234, Seabee Combat
Handbook, Vol. 1
Claymore Mines
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Placement
– This mine should be positioned so as to afford all friendly personnel, within 100 meters
to the rear and sides of the mine, the opportunity to take adequate cover.
Arming
– After the M18A1 mine is positioned and properly aimed, it is armed by first opening the
blasting cap assembly and unrolling the wire from either the firing position or the mine.
– The wire is secured by wrapping a few turns of wire around a leg of the mine and burying
it, if possible.
Safety requirements
– Before attaching the firing device directly, the circuit should be checked for continuity
with the test set provided to ensure that the mine will function at the desired time
– The firing device has a safety bail with two positions
– In the upper (safe) position, it acts as a block between the firing handle and the
generator.
– In the lower (fire) position, it allows the generator to be activated.
– The instructions provided with the M7 bandoleer should be carefully followed by anyone
using these mines.
Claymore Mines
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Range/Coverage
– When detonated, the M18A1 mine will project steel spheres over a 60 degree
fan shaped pattern approximately 6 feet high and 50 meters wide to an
optimum effective range of 50 meters
– These steel fragments re moderately effective up to a range of approximately
100 meters and can travel up to 250 meters
Method of firing
– M18A1 mine can be in either an uncontrolled or a controlled role. An
uncontrolled mine is essentially a booby-trap. This use by Seabees is not
authorized. In a controlled role, the operator detonates the mine as the
enemy approaches within the killing zone
– By using either an electrical or a non-electrical firing system, the operator can
control detonation.
– In almost all cases, mines employed by Seabees will be fired electrically with
the M57 firing device.
M240B
• PQS Question 108.14 Explain the
characteristics of the machine gun [ref l, ch. 3]
Reference: FM 3-22.68
M240B
• Air-cooled, Belt-fed, Gas-operated, Fully Automatic
weapon, Fires from open bolt Position and is Crew
served
– Length................................49 inches
– Weight ...............................27.6 pounds
– Maximum range ................3,725 meters
Loading/Unloading
PQS Question 108.15 Discuss loading/unloading procedures
[ref l, ch. 3]
Reference: FM 3-22.68
Loading/Unloading
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The M240B machine gun is loaded from the closed bolt position. The M240B is fired, unloaded, and
cleared from the open bolt position. The safety must be placed on “F” before the bolt can be pulled to the
rear. Before belted ammunition can be used, it must be linked with the double link at the open end of the
bandoleer. It must be free of dirt and corrosion.
Loading – Two methods, raised cover and closed cover
– Raised cover method – preferred method
• Gunner ensure the bolt is to the rear and the safety lever is on safe (S)
• Gunner raises the cover
• Team leader places the first round of the bandoleer and places it over the feed aperture
• Gunner then closes the cover and places the safety lever on fire (F)
• Weapon is now loaded and ready to fire
– Closed cover method – alternate method
• Gunner ensures bolt is forward safety lever is on fire (F) and the cover remains closed
• Team leader takes a bandoleer of ammunition and inserts the first round into the feedtray
• The weapon is now loaded
• Gunner pull bolt to the rear and slides cocking handle forward – The weapon is now ready to
fire
Loading/Unloading
• Unloading
– Gunner ensures bolt is to the rear and the safety is on
safe (S)
– Gunner raises the cover
– Team leader removes the ammunition and links from the
feedtray
– Gunner then raises the feedtray and visually inspects the
receiver and chamber to ensure no rounds remain
– Once the feedtray, receiver and chamber have been
cleared of all ammunition and links the weapon is
considered to be unloaded
Capabilities/Nomenclature
• PQS Question 108.16 State the following
capabilities/nomenclature
Proper employment [ref l, ch. 3]
FPL/PDF [ref l, ch. 5]
Maximum effective range [ref l, ch. 3]
Safeties M240B [ref l, ch. 3]
Ammunition types [ref l, ch. 3]
Rates of fire [ref l, ch. 3]
Types of mounts [ref l, ch. 3]
Capabilites/Nomenclature
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Proper employment
– Analyze the operation order using METT-T SALUTE DRAW-D and KOCOA
– Consider the characteristics of the machine guns to be employed
– Consider employment of the machine guns in defense
– Consider employment of machine guns in the offense
– Direct the employment of the machine guns
Final Protective Line (FPL)/Principal Direction of Fire (PDF)
– Assignment of a Final Protective Line (FPL)
• Position machine guns to the flanks to provide fire across the unit's
front.
• Ensure the position provides interlocking grazing fires within an
assigned sector
• Ensure that FPL dead space can be covered by alternate weapons
(munitions, M203 grenade launchers, mortars, claymore mines)
– Assignment of a Principal Direction of Fire (PDF)
• Ensure the position covers likely avenues of approach and obstacles
– Maximum effective range: 1,100 meters with tripod and T&E
Nomenclature
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• Area
– Tripod..................................................1,100 meters
– Bipod...................................................800 meters
• Point
– Tripod..................................................800 meters
– Bipod...................................................600 meters
– Suppression...............................................1,800 meters
Safeties
• The safety mechanism is located on the pistol grip just behind the trigger well.
When the safety is pushed to the right, the letter “S” is visible indicating the
weapon is on safe. When pushed to the left, the letter “F” is visible on the safety
indicating the weapon is on fire. The safety can only be engaged when the bolt is
in the rear position. On the “S” position, the bolt cannot be released to go forward.
Ammunition types
• 7.62 mm ball
• 7.62 mm tracer
• 7.62 mm armor-piercing (not authorized for training)
• 7.62 mm blank
• 7.62 mm dummy
Rates of Fire
– Rates of fire
• Sustained ..............................100 rounds per
minute fired in 6- to 9-round bursts and 4 to 5
seconds between bursts (barrel change every
10 minutes)
• Rapid......................................200 rounds per
minute fired in 10- to 13-round bursts and 2 to 3
seconds between bursts (barrel change every 2
minutes)
• Cyclic ………………………….650 to 950
rounds per minute in continuous bursts (barrel
change every minute)
Types of Mounts
– Types of mounts
• M122A1 Tripod: provides a stable mount for the M240B,
and it permits a higher degree of accuracy and control.
The tripod is recommended for marksmanship training
and defensive employment. The M122A1 tripod consists
of the tripod and flex-mount with T&E mechanism.
Weight of M122A1 tripod with/flex-mount is 20 pounds.
• Bipod Assembly: used to fire from the prone position.
The butt stock in conjunction with the gunner’s non-firing
hand provides support for the weapon when firing in the
bipod mode. The gas cylinder holds the bipod in place.
Members of a Gun Team
• PQS Question 108.17 Name the members of a gun team
and state what they are responsible for carrying into a
combat situation
• Reference: [ref a. p. 1-17]
NAVEDTRA 14234, Seabee Combat Handbook, Vol 1
Gun Team
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Team leader
– Usually a PO2, responsible for effective employment of the gun
– Responsible for changing the barrels during firing
– Carries spare barrel kit, M122 tripod, one bandoleer of ammo and armed
with a 9mm pistol
Gunner
– Usually a PO3. Actually fires and maintains the gun
– Carries the gun, one bandoleer of ammo and armed with a 9mm pistol
Ammo 1
– Usually a CN, acts as the supply person for the team
– Caries one box of ammo, spare barrel case with T&E. Armed with an M16
Ammo 2
– Usually a CA
– Carries two boxes of ammo. Armed with an M16
Weapons Fundamentals
• PQS Question 108.18 Describe the
characteristics of 40mm Machine Gun
• Reference: [j]
TM 9-1010-230-10
40 mm Machine Gun
40 mm Machine Gun
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Air-cooled
Belt-fed
Blow back operated
Automatic weapon
Fires from open bolt position
Crew served
Weapons Fundamentals
• PQS Question 108.19 Discuss
loading/unloading procedures for the 40mm
Machine Gun
• Reference: [j]
TM 9-1010-230-10
40mm Machine Gun
Loading
• Keep the weapon down range
• Make sure the bolt is forward. If not take the
weapon off safe and ease the charging
handles forward.
• Open the cover
• Insert the first round through the feed throat
40mm Machine Gun
Loading
• Insert the first round through the feed throat
• Place the first round into the feeder. Female
link first.
• Push the round across the first pawl
• Move the slide assembly to the left
40mm Machine Gun
Loading
• Close the cover
• Unlock and grasp the charging handles
and charge weapon
40mm Machine Gun
Un-Loading
• Place weapon on safe
• Open cover
• Remove remaining rounds and inspect
chamber
• Once clear, close cover
40mm Machine Gun
Un-Loading
• Place weapon on fire and use charging
handles to “ride” bolt forward or press
trigger sending the bolt forward.
Weapons Fundamentals
• PQS Question 108.20 State the following
capabilities/nomenclature of the 40mm Machine
Gun.
* Proper employment [ref m, ch. 6, sec l]
* FPL/PDF [ref m, ch. 6, sec l]
* Arming Range [ref j]
* Maximum effective range – area [ref j]
* Maximum effective range – point [ref j]
* Rate of fire [ref j]
* Safety [ref j]
* Ammunition Types [ref j]
Weapons Fundamentals
•
Proper employment
– Conduct a leader's reconnaissance of the assigned area.
– Consider placing firing positions in areas where the mission can be
accomplished.
– Look for mounted firing positions.
– Choose dismounted firing positions when the terrain prevents
vehicles from moving into position or if the vehicle cannot be
concealed.
– Identify firing positions.
– Move vehicle into position
– Ensure that the machine guns are properly laid.
– Ensure that the firing positions are properly prepared and occupied
– Ensure that range cards are prepared for each position.
FPL/PDF
•
FPL/PDF
– NOTE: The MK19 heavy machine gun does not fire an FPL.
– Assign a Principal Direction of Fire (PDF)
• Assign a PDF only when the terrain does not allow for effective
FPL fires.
• Ensure the PDF covers the most likely avenues of approach.
• NOTES: The PDF may fall within the sector of fire or comprise
one of its boundaries.
– Location of machine guns must be changed daily/nightly or
whenever needed.
40mm Machine Gun
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Arming range
– M383 HE round: 18 to 36 meters
– M918 TP round: 18 to 30 meters
Maximum effective range
– (area target) – 2212 meters
– (point target) – 1500 meters
Rate of fire – 325 to 375 rounds per minute
Safety
– Thumb switch with “Safe” and “Fire” positions
Ammunition types
M383 HE: High explosive, designed to inflict personnel casualties.
Arming distance of 18 to 36 meters. 15 meter casualty radius
– M430 HEDP: High explosive, dual purpose
– M385E4 / M385A1: Training Practice with propellant. Maximum
range 2200 meters
Weapons Fundamentals
• PQS Question 108.21 Describe the
characteristics of the .50 caliber M2 machine gun
Reference: [k, ch. 1, sec ll, p. 1-5]
TM 9-1005-213-10
M2 Machine Gun
M2 Machine Gun
• The .50-caliber machine gun is a belt-fed,
crew-served, recoil-operated, air-cooled
weapon.
• It can be set for automatic and semiautomatic
fire.
• The weapon does not have any safeties.
Weapons Fundamentals
• PQS Question 108.22 Discuss
loading/unloading procedures for the M2
Machine Gun
• Reference: Reference:
[k, ch. 1, sec ll, p. 1-5]
TM 9-1005-213-10
M2 Machine Gun
Loading
Automatic mode
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•
•
•
•
Make sure gun is clear
Close the bolt
Close feed cover
Lock down the bolt latch release
Insert the ammo
M2 Machine Gun
Loading
• Cock the gun (the gun is now “half-cocked”)
• Re-cock the gun (now it is “fully-cocked”)
M2 Machine Gun
Loading
Single shot mode
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•
•
•
Make sure gun is clear
Close the bolt
Close feed cover
Rotate bolt latch release lock in the up
position to the right
M2 Machine Gun
Loading
• Insert the ammo
• Cock the gun (the gun is now “half-cocked”)
• Re-cock the gun (now it is “fully-cocked”)
• To fire another round you must push the bolt
release allowing the bolt to go home
M2 Machine Gun
Un-Loading
• Place the gun in single shot mode
• Pull slide handle to the rear and lock bolt
rearward
• Open the feed cover
M2 Machine Gun
Un-Loading
• Clear all remaining links or rounds
• Inspect chamber insuring it is clear
• Press the bolt latch release and ride the bolt forward
• Close the feed cover and pull the bolt to the rear
Weapons Fundamentals
• PQS Question 108.23 State the following
capabilities/nomenclatures
* Proper employment [ref m, ch. 6, sec l]
* FPL/PDF [ref m, ch. 6, sec l]
* Arming Range [ref m, ch. 6, sec l]
* Maximum effective range – area [ref k, ch 1, sec ll, p. 1-9]
* Maximum effective range – point [ref k, ch 1, sec ll, p. 1-9]
* Direction of feed [ref k, ch 1, sec ll, p. 1-9]
* Rates of fire [ref k, ch 1, sec ll, p. 1-9]
Weapons Fundamentals
•
Proper employment
– Conduct a leader's reconnaissance of the assigned area.
– Consider placing firing positions in areas where the mission can be
accomplished.
– Look for mounted firing positions.
– Choose dismounted firing positions when the terrain prevents
vehicles from moving into position or if the vehicle cannot be
concealed.
– Identify firing positions.
– Move vehicle into positions.
– Ensure that the machine guns are properly laid.
– Ensure that the firing positions are properly prepared and occupied.
If you must use a hide position, perform the following steps.
– Ensure that range cards are prepared for each position.
M2 Machine Gun
•
FPL/PDF
– FPF
• Ensure that the FPL achieves the maximum flanking fire.
• Ensure that the FPL obtains the maximum grazing fire. Grazing
fire should parallel the expected long axis of the enemy assault
waves.
• Ensure interlocking fires are used to cover any gaps in the FPL
and to provide mutual support between adjacent units.
• Employ obstacles to slow down the enemy when reaching the
FPL, if possible.
– PDF
• Assign a PDF only when the terrain does not allow for effective
FPL fires.
• Ensure the PDF covers the most likely avenues of approach.
M2 Machine Gun
• Maximum range – 6800 meters (M2 Ball)
• Maximum effective range – 1800 meters
• Direction of feed – Load so double end loop
on ammo belt clicks into the feedway.
• Rates of fire
– Sustained: 40 rounds (or less) per minute
– Rapid: 40 rounds (or more) per minute
– Cyclic: 450 – 550 rounds per minute
Weapons Fundamentals
• PQS Question 108.24 Describe setting
headspace and timing on the .50 caliber
machine gun
• Reference: [k, ch. 2, sec lll, p. 2-39]
TM 9-1005-213-10
M2 Machine Gun
Headspace
 Headspace - Distance between the bolt face
and the base of a seated cartridge (rnd).
 Correct when:
– Recoiling groups are fully forward
– No independent rearward movement
between the bolt, barrel and barrel
extension
M2 Machine Gun
Headspace
–Must be checked and set before gun is
fired,
–When barrel is replaced and
–When correct setting is in doubt
M2 Machine Gun
Headspace
• Headspace Gauge
• Tool used to check and set headspace
• Has “GO-NO GO” reading
M2 Machine Gun
Headspace Adjustment
• Insert the “GO” side of the gauge between the
bolt and rear of the barrel (T-slot)
• The gauge should enter freely up to the
center ring
• Remove the gauge and place the “NO-GO”
side in the T-slot
• If the “NO-GO” side does not enter, the
headspace is set correctly
M2 Machine Gun
Headspace Adjustment
•
•
•
•
Headspace Too Tight
The “GO” side of the gauge cannot enter freely
Pull back on the charging handle
While holding it back, unscrew the barrel one
notch (click)
• Ease the bolt forward
• Recheck the headspace with the gauge
M2 Machine Gun
Headspace Adjustment
• Headspace Too Loose
• If it is too loose the “NO-GO” side of the
gauge will enter freely
• To adjust it follow the same procedures as if it
were to tight, but tighten the barrel
M2 Machine Gun
Timing
• Timing - Ensures that firing takes place
when the recoiling parts are between
.020 and .116 inch out of the battery
(fully forward).
M2 Machine Gun
Timing
 Correct when:
– recoiling parts are locked together
– Firing takes place just before the
recoiling parts are in the battery
– The gun fires on the “FIRE” gauge
– And WILL NOT on the “NO-FIRE”
gauge
M2 Machine Gun
Timing Adjustment
• Timing Adjustment
• Checked with the “FIRE” (.020 in) and “NOFIRE” (.116 in) gauges
• Must be checked and/or set each time
headspace is adjusted and whenever timing
is questionable
M2 Machine Gun
Timing Adjustment
• Timing Adjustment Steps
•
•
•
•
Check headspace first
Ensure gun is cocked and bolt forward
Raise the extractor
Retract the bolt far enough to insert the
“FIRE” gauge
M2 Machine Gun
Timing Adjustment
• Timing Adjustment Steps Continued
• Place it between the extension and the
trunnion block
• Allow the barrel extension to close on the
gauge
• Depress the trigger, the firing pin should
release
M2 Machine Gun
Timing Adjustment
• Retract the bolt far enough to remove the “FIRE”
gauge, cocking the gun and allow the bolt to go
forward
• Retract the bolt far enough to insert the “NO-FIRE”
gauge, place it in the same position
• Depress the trigger, the firing pin should not release
M2 Machine Gun
Timing Adjustment
• Timing Late
• The firing pin will not release when the “FIRE”
gauge in in place. If this happens perform the
following:
• Remove “FIRE” gauge
M2 Machine Gun
Timing Adjustment
• Remove backplate assembly
• Locate and turn the trigger bar adjusting nut
one notch to the right
• Reinstall the backplate assembly
• Reinsert the “FIRE” gauge and test again
M2 Machine Gun
Timing Adjustment
• Timing Early
• The firing pin will release when the “NOFIRE” gauge in in place. If this happens
perform the following:
• Perform the same steps as if it were late
except turn the trigger bar adjusting nut on
notch to the left
Weapons Fundamentals
• PQS Question 108.25 Describe the
characteristics of the 40mm M203 grenade
launcher
• Reference: [i] Construction Battle Skills
Guide, Book 4, Crew/Team Skills
40mm Grenade Launcher
40mm Grenade Launcher
• Description
– Light weight
– Single shot
– Breech loaded
– Pump action
– Shoulder fired weapon
– Attaches to the M16 rifle
Weapons Fundamentals
• PQS Question 108.26 State the following
capabilities/nomenclature
* Proper Employment
* Ammunition Type
* Maximum effective range (area)
* Maximum effective range (point)
* Maximum range
• Reference: [a] NAVEDTRA 14234, Seabee Combat
Handbook, Vol. 1.
Capabilites/Nomenclature
– Proper employment
• Place the weapon in condition 4
• Ensure that the M203 grenade launcher is assembled and
functioning for firing.
• Select the correct ammunition.
• Place the weapon in condition 4.
• Use proper firing techniques.
• Field zero the M203 grenade launcher.
• Estimate range to target.
• Respond to fire commands.
• Engage targets effectively.
• Place the weapon in condition 4.
Capabilities/Nomenclature
– Ammunition type [ref. a, p. 13-4]
• HE round
– Designed to inflict personnel casualties. 5 meter casualty radius
with a danger radius of 30 meters. Arms within 14 meters to 27
meters.
• HE air burst
– Lands on the deck and bounces up 2 meters to explode. Arms
within 14 meter to 27 meters.
• HEDP
– High explosive, can penetrate 2” of steel. 5 meter casualty radius
• TP
– Training rounds with flash signature. Danger radius of 20 meters.
– Maximum range [ref. a, p. 13-1] – 400 Meters
– Maximum effective range
• (area target) [ref. a, p. 13-1] – 350 Meters
• (point target) [ref. a, p. 13-1] – 150 Meters
Weapons Fundamentals
• PQS Question 108.27 Describe the
characteristics of the M500 12-gauge shotgun
• Reference: [h, p. R3-19]
TM-SW215-B4-MMO-010
M500 12 Gauge
Shotgun
12-Gauge Shotgun
Operation
•
•
•
•
•
Manually operated
Single shot
Magazine feed (tubular)
Pump action
Shoulder fired weapon
Weapons Fundamentals
• PQS Question 108.28 Describe loading and
unloading procedures for the 12-gauge
shotgun.
• Reference: [h, p. R3-20]
TM-SW215-B4-MMO-010
12-Gauge Shotgun
Loading
• Single Load
• Ensure the weapon is on safe
• Press the action lock lever and slide barrel
(fore-end) rearward
12-Gauge Shotgun
Loading
• Insert round into the barrel chamber
• Slide the barrel closed
• Weapon is now loaded
12-Gauge Shotgun
Loading
Magazine Load
• Ensure the weapon is on safe
• Slide barrel (fore-end) forward
• Insert round into the magazine
12-Gauge Shotgun
• Loading
– Weapon is now loaded without round in
chamber
– Open and close barrel to chamber a round
• Unloading
– Open barrel to eject round to unload
Weapons Fundamentals
• PQS Question 108.29 State the following
capabilities/characteristics of the 12 gauge
shotgun.
– Length
– Safeties
– Ammunition type
• Reference: [h, p. R3-20]
TM-SW215-B4-MMO-010
12-Gauge Shotgun
• Length: 39 inches
• Safeties: Safety switch on top
• Ammunition type: 12 ga, 2 - 2 3/4 in 00 buck,
military round
Weapons Fundamentals
• PQS Question 108.30 Describe the use and
purpose of the range card as it relates to
each weapon system.
• Reference: [i, ch. 4]
Construction Battale Skills Guide, Book 4
Range Cards
– Cards are the basis for the fire plan at
the company level. Each crew served
weapon will have one.
– All supporting fires, security sectors and
defensive coordination are planned using
the machine gun’s fire as the base from
which to build.
Range Cards
– Two cards are prepared, one for the gun
and the other goes to higher HQ.
– Cards should be passed on to relieving
units.
– Patrols can use your card to locate FPL’s
and identify dead space.
– Cards must be neat and prepared using a
universal format.
Range Cards
• Gun Identification Block - Identifies
what gun the card belongs to and the
date it was drawn.
Gun #1
Squad #3
"A" Co
5-Apr-99
Range Cards
• Weapon Symbol - Single dot for the
gun and a solid arrow extending out
along the FPL or PDF.
Range Cards
• Magnetic Orientation Line and Location Grid
Coordinates - A means for others to positively
locate your gun position. The line is drawn
from a prominent terrain feature that is located
behind friendly lines. The grid coordinates are
recorded next to the dot in the machine gun
symbol.
Range Cards
• Sector Limits - Drawn as broken lines
ending in arrow heads. If using an FPL
only one sector limit will be drawn
because one will be the same as the
FPL.
Range Cards
• Grazing Fires - If an FPL is used, a heavy shaded
area is drawn along the inside of the FPL. This will
indicate the limits of grazing fire obtainable. Any
dead space is shown by breaks in the shading.
Record the near and far limits of the dead space in
meters or record the range next to the ends of the
shaded areas.
Range Card Symbols
• Terrain Features - Draw only those terrain
features that significantly add to the clarity of
the range card. If the feature is drawn, draw
it to the correct perspective.
• Wooded area
hill
Range Card Symbols
• Location of Friendly Troops or Equipment
- Draw any friendly positions or equipment
that is either in or near the sector limits of the
machine gun.
1st Sqd
Water tower
Range Card Symbols
• Targets - Draw targets to perspective and
label them with a number.
– The number one target will be either the FPL
or the left sector limit.
– If the FPL is on the right sector limit, number
all other targets sequentially from right to left.
– All other times number from left to right.
Range Card Symbols
– One method is to record data directly
on the sketch along the leading line to
the target.
– The other method is to use the data
block of the card.
Sample Range Card
•
2
AB100
1
400
m
300m
1st Sqd
2nd Sqd
3rd Sqd
Weapons Fundamentals
• PQS Question 108.31 Discuss the
integration of the weapons systems into an
overall defensive fire plan.
• Reference: [i, ch. 4]
Construction Battale Skills Guide, Book 4
Weapons Systems
Integration
•
•
•
•
Automatic Rifleman
– M16 rifle, backbone of the defense of the squad. Positioned first by
the squad leader. The remainder of the fire team is positioned
around the AR.
Rifleman
– M16 rifle, positioned so they can cover the entire fire team sector.
The position must provide support and protection for the AR
Grenadier
– M203 grenade launcher, positioned to cover dead space in the
defense
M240B
– Support the rifleman in the offense and defense. Provide heavy
volumes of controlled fire. Provide FPF’s. Cover likely avenues of
approach. Provide grazing fire.
Weapons Systems
Integration
• M2 .50 Cal Machine Gun
– Provide protection for motorized movement.
Destroy lightly armored vehicles. Defend against
low-flying hostile aircraft
• MK19 40mm Grenade Launcher
– Used to provide direct and indirect firing. Role is
similar to the M60E3 and M2.
• AT-4
– Used against armored personnel carriers. Can be
used to disable a battle tank (mobility kill) if struck
properly.
Weapons Fundamentals
• PQS Question 108.32 Describe the use and
purpose of the following Night Observation Devices.
* AN/PVS-7C (night goggles)
* AN/PVS-12A (M240B, M16, M14)
* AN/PVS-20 (MK19, M2)
Reference: [c]
Seabee Battle Skills Guide, Vol. 1
AN/PVS-7C
Night Vision Devices
AN/PVS-7C (Night Goggles)
• AN/PVS-7C - Hand held or head mounted
night vision system that enables walking,
driving, weapon firing, short range
surveillance, map reading and vehicle
maintenance in both moonlight and starlight.
• Range - min 9.8”
AN/PVS-12A
• AN/PVS-12A (M240B, M16, M60, M14)
– The AN/PVS-12A, Night Vision Individual Weapon Sight
System provides the infantry and support weapons with high
performance observation, target acquisition and aiming
capabilities during night operations. The Sight is capable of
focusing on targets from 82 feet to infinity. The AN/PVS-12A
is submersible, which permits the transportation of the
AN/PVS-12A unprotected in two (2) atmospheres (66 feet) of
seawater. The Sight is a high performance night vision
system for nighttime target acquisition. The Sight uses a
GEN III, 18 mm image intensifier tube configured in
accordance with MIL-I-49428. Mounting hardware, which
can easily be changed to other type mounts, are provided for
attachment to the M16 and M14 Rifles.
AN/PVS-20
• AN/PVS-20 (MK19, M2)
– The AN/PVS-20, Night Vision Individual Weapon
Sight System provides the infantry and support
weapons with high performance observation,
target acquisition and aiming capabilities during
night operations. The Sight is capable of focusing
on targets from 82 feet to infinity. The AN/PVS-20
can be used on the M2 .5 Cal. Machine Gun, and
Mk38 Mod 0 25mm Machine Gun System.
Mounting brackets and reticule cells are available
for each type of weapon. The Sight may also be
used as a tripod mounted observation device.
Classes of Fire
• PQS Question 108.33 Explain the various classes of fire:
* Grazing
* Plunging
* Overhead
* Fixed
* Traversing
* Searching
* Combine searching and traversing
* Swinging traverse
* Free
Reference: [e]
Construction Battle Skills Guide, Book 1
Classes of Fire
•
•
•
•
•
•
Grazing
– Not less than 1m above and no higher than 68” above the ground. Can
exist for 700m over level or evenly sloping ground
Plunging
– Fire that strikes the ground from above at a considerable level. Beaten
zone is considered the danger space.
Overhead
– Fire delivered over the heads of troops. Usually plunging fire overhead.
Fixed
– For targets requiring only one aiming point. Continuous as long as target
remains in the zone of fire
Traversing
– Distributed in width by changing the horizontal direction of the gun. Firing a
burst each time the gun changes direction
Searching
– Distributed in depth by changing the elevation of the gun. Used against
deep targets, firing a burst each time elevation changes
Classes of Fire
• Combined searching and traversing
– Distributed in width & depth by changing the elevation
direction of the gun.
• Swinging traverse
– Delivered against targets to wide to cover the traversing
hand wheel. Also used on targets moving so rapidly across
the gunner’s front they cannot maintain effective fire using
the traversing hand wheel . Cannot be fired from bipod or
vehicles.
• Free
– Delivered from the tripod mount against targets requiring
rapid and major changes in direction and elevation. Can also
be used from a vehicle mount when the target cannot be
covered adequately by aiming points. Cannot be fired from
bipod mount.