Gun Block (copy)

Prohibited Items

Rings

PPE Required for wear during weapons employment

Gloves, Helmet, Hearing Pro, Glasses

Munitions operations are…

Inherently dangerous activities including upload and download

Required Items

Adequate lighting, 150lb Fire bottle or equivalent,

Dropped Ammo Procedures

Dropped Ammo must be marked and returned to ammunition personnel

Fire involving Ammo

Notify the crew and fire department, then simultaneously fight the fire, remove ammo if possible. Withdraw all non essential personnel 2500 feet. WHEN fire envelops munitions, crew members fighting the fire will also withdraw 2500 feet

Withdraw distances for fire involving ammo

Withdraw all non-essential personnel 2,500feet withdraw to 4,000 feet when net explosive weight exceeds 500lb of high explosive class ammo

When are weapons Inspections conducted?

Prior to flight as well as both before and after each mission

Purpose of weapons inspections

serves to verify the weapon is clear of ammunition or spent casings and is in a safe configuration. Function checks ensure the weapon is serviceable

Prior to weapons inspections, VERIFY the weapon is:

Safe- Proper weapon configuration

Serviceable- Performing function checks

Clear- Visually inspect for ammo/brass in chamber

What is a weapon malfunction?

Failure in the firing cycle due to improper timing or broken components

SMA’s are responsible for diagnosing and repairing

Gun Stoppage or “Bent Gun”

Interruption in the weapons firing cycle

Hot Gun

If rounds are present in the barrel or chamber, and the potential for inadvertent firing exists

Misfire

Weapon fails to fire after the trigger is pulled

• usually do to a malfunction within the propellant explosive change

• treat as hang fire until potential for inadvertent firing is eliminated

Hang Fire

Delay between trigger pull and the weapon firing due to propellant charge igniting slower than usual

• fraction of a second to several seconds dependent on type of ammo

Cook off

Inadvertent firing (without pulling the trigger) after the propellant charge is ignited by a hot barrel or chamber

• common after long firing bursts due to the heating of gun components, especially in single barrel weapons

Runaway Gun

Continues firing after the trigger is released

• due to failure in some portion of firing mechanism

• will continue until weapon is empty or some other weapon malfunction occurs

What is the function of a weapon?

to deliver a destructive force on an enemy target

What is Caliber?

Measurement representing the diameter of a round

• measured in inches, hundredths of an inch, or millimeters

Three categories of a bullets

Light- less than 20mm

Medium- 20mm-100mm

Heavy- Greater than 100mm

Cartridge

Packages the bullet, gunpowder, and primer into a single case made to fit down the chamber of the barrel

• seals firing chamber in all directions except down the barrel

Fuze

Mechanical OR electrical detonation device for setting off the bursting charge of a projectile

• often used on large caliber projectiles that contain explosives

• Requires SETBACK (inertia) and spin to arm

Full Metal Jacket (FMJ)

Encased in a copper coated steel

• prevents damage to barrel

• reduce deformation of the bullet (reducing misfires)

• prevent fragmentation within its target

Ogive

Curved portion of a projectile between fuze and the bourrelet

Bourrelet

forward bearing surface of a projectile

• centers forward art of the projectile in the tube

• Only the bourrelet and the rotating band of the projectile contact the grooves of the barrel

Body

Cylindrical portion of the projectile between the bourrelet and the rotating band

• contains most of the explosive filler

Rotating band

Seals the bore (chamber)

Responsible for imparting spin on the projectile by following the rifling as it travels through the barrel

• positions and centers the rear end of the projectile in the chamber

Base

Portion of the projectile below the rotating band

• squared or more commonly- “boat tailed”

Tracer

Small pyrotechnic charge in the base

Base Plate

Metal cover that is crimped, caulked, or welded to the base of the projectile

• prevents hot gasses of the propellant charge from prematurely heating

Propellant Explosive Train

Sequence of events and associated components leading to the detonation of a propellant charge

Consists of:

1) Primer- small metallic cap sensitive to friction, heat, electricity, or shock

2) igniter- Ignited by primer ignites propellant charge

3) Propellant

Primer

Small metallic cylinder cap containing