American Projectiles and Explosives - Navy Rockets (Part 3)

American Projectiles and Explosives

Navy Rockets






4.5-inch B.R.

(With Head Mk 3)

Overall length: 30 inches

Weight: 28.7 pounds

Head length: 18 inches

Head weight: 19.9 pounds

Wall thickness: 0.25 inches

Motor length: 15.5 inches

Motor diameter: 2.25 inches

Range: 1,000-1,100 yards

Weight of TNT charge: 6.5 pounds

Fuze: Mk 137 or Mk 145

General: The 4.5-inch Barrage Rocket is a light demolition rocket intended for launching from landing boats, from amphibious trucks, or from portable launchers of one or more rails.


Head: The head and motor are coupled by means of a threaded adapter, and the fuze screws into the nose of the head.  The head is cylindrical, the forward and hemispherical and the read end reduced.  About 6.5 pounds of high explosive can be loaded through a 2 and 3/4 inch hole in the rear, which is sealed later with a motor adapter.  The fuze liner, in the nose of the head, contains a booster charge of granular TNT.

Tail Assembly: Two circular shrouds, the same diameter as the body, are attached to supporting fins at the rear of the motor.  Two wires brought out through the powder grain and the nozzle connect to the two shrouds.  The forward shroud is insulated from the rest of the rocket to prevent a short-circuit to the after grounded shroud.

Propellant: The propellant consists of a single cylindrical grain of ballistite 11 inches long, with a 1.7 inch outer diameter.

5-inch A.R. with 5-inch motor

Overall length: 69 inches

Weight: 140 pounds

Head length: 20.3 inches

Head diameter: 5 inches

Head weight: 52 pounds

Motor length: 51.4 inches

Motor diameter: 5 inches

Velocity: 1,350 feet/sec

Fuzes: Mk 5 Mod 0 and Mk 6 Mod 0

-Nose Fuze Mk 148

-Nose Fuze Mk 149

-Base Fuze Mk 157 Mod 0

-Base Fuze Mk 159 Mod 0

Mk 6 Mod 1

-Base Fuze Mk 159 Mod 1

-Base Fuze Mk 164 Mod 0

Head: The Head Mk 6 Mod 0 is filled with TNT and is equipped with a base fuze and a nose plug.  When thus used, the head will have the penetration and fragmentation characteristics at comparable velocities of the 5"/38 AA Common projectile, of which it is a modified design.  All 5-inch Rocket Heads Mk 6 Mods 0 and 1 are shipped with a base fuze installed and staked in place.  No attempt shall be made to remove the base fuze from the head prior to the firing.  A metal cup-shaped thread protector covers the external threads on the base of the head and on the base fuze.

The Mk 6 Mod 1 is similar to the Mk 6 Mod 0, with a gas seal added to the bomb-fuze seat.  The 5-inch Body Mk 5 Mod 0 is the initial California Institute of Technology production, which was adopted by Bureau of Ordnance as the Mk 6 Mod 0.  The two bodies are identical.

The 5-inch Aircraft Common Mk 2 Mod 1 is a new head designed to achieve greater penetration.  This penetration is expected to be two to three inches of homogeneous armor plate at launching speeds of 1,500 feet per second.  The head has a total weight of 48.1 pounds, is 14 inches long, and contains a filler of 2.66 pounds of Explosive "D".  The nose is heavy and solid.  A base fuze (the Mk 166 Mod 0) will be shipped installed.  This head will fit any of the 5-inch motors.

The Head Mk 2 Mod 2 has no adapter and has Acme thread; otherwise it is the same.

Motor: The 5-inch Motor Mk 2 Mod 0 consists of a seamless steel tube with internal threads on both ends.  Into the rear end is screwed the nozzle plate having eight nozzles arranged in a circle, and a central blow-out nozzle.  The central nozzle is closed by a disc of 0.024-inch thick copper, insulated against the heat of the motor by asbestos and hard fiber plugs.  The thickness of the disc is such that it shears and blows out at a pressure of approximately 2,400 pounds per square inch, which is the normal maximum motor pressure when the propellant grain is at a temperature of 100 degrees Fahrenheit.  If the pressure rises above this, the disc and plug are ejected; this increases the usable temperature range of the rocket by about 40 degrees Fahrenheit.

Seven of the eight nozzles are sealed individually by a light steel cup and sealing compound.  The eight nozzle accommodates the electric connector cable, which is crimped into the steel nozzle closure.  In shipment, a dome-shaped steel shipping cap fits into the sleeve of the fin assembly, acting as an auxiliary seal and at the same time serving to enclose and protect the electrical pigtail in shipment.

Lugs for attaching the fins are mounted on the nozzle end of the motor.  The fins are shipped with the motor and are attached when the round is assembled.  The fins are held in place by spring-loaded latches within the fin itself.  The fin lugs and rear suspension lugs are welded to the bands of the fin assembly, which is slipped on over the nozzle end of the motor.  The front lug band is strapped to the motor.  The motor is shipped with lug attachments on the motor tube for use with Aircraft Launcher Mk 5 Mod 1.  An extra rail-type lug is provided in the shipping box to adapt the rocket for use on the Aircraft Launcher Mk 4.

The front end of the motor is sealed by a steel diaphragm equipped with a blow-out disc in the center to allow easy passage of the motor gases to the pressure-arming fuze in the base of the body.  In shipment, a cylindrical metal thread protector extends into the motor the same depth as the body and seats on a felt rim glued to the diaphragm seal.

The propellant is a grain of cruciform ballistite weighing 24 pounds.  The grain is inhibited on the outer web surface and is supported by a spacer and a steel grid at the nozzle end.  The propellant is ignited by a metal case igniter containing 35 grams of black powder.

The 5-inch Motor Mk 2 Mod 1 was never produced.  The Mk 2 Mod 2 differs in that the tail fins are welded to a sleeve which slips over the base of the tube and is clamped in place.  The fin assembly is complete and separate from the motor.  The rear suspension lug for use with the Launcher Mk 5 Mod 1 is on an independent band.  The Mk2  Mod 3, which will supersede the Mods 0 and 2, is similar to the Mod 2, except that the nozzle ring is of slightly different construction.

The 5-inch Rocket Motor Mk 1 Mod, California Institute of Technology production, is the prototype of the Mk 2 Mod 0, Bureau of Ordnance issue.  The two motors vary only in that the suspension lugs on the former are welded directly to the rocket motor.

5-inch S.S.S.R.

General: The General Purpose and Common rounds are particularly adapted for repelling PT-boat attacks at ranges less than 11,000 yards.  The High-Capacity rockets are suitable for barrages at 1,250 to 5,000 yards.  These rockets must be used in the specially designed Launchers Mk 50 Mods 0 and 1 and Mk 51 Mods 0 and 1; and in Launcher Assemblies Mk 101 Mod 0 or Mk 102 Mod 0.



Heads

5-inch Head Mk 7 - General Purpose: This head is threaded externally at the after end to accommodate the motor.  It is threaded internally at the forward end to accommodate the fuze adapter for Rocket Fuze Mk 100 and Mods.  Two spanner holes are located in the after end of the head spaced 180 degrees apart to facilitate assembly.  The fuze adapter is internally threaded for Auxiliary Detonator Fuze Mk 44 Mod 2.  The Nose Fuze Mk 100, all Mods, is screwed in over the Auxiliary Detonating Fuzes.  (The fuze adapter and an Auxiliary Detonator Mk 44 Mod 2 are shipped installed in the head.)


5-inch Head Mk 8 and Mods - Common: The head is internally threaded at the after end to take Base Fuze Mk 31.  It has two spanner holes 180 degrees apart to facilitate assembly operations.


5-inch Head Mk 10 and Mods - High Capacity: The nose of this head is internally threaded to fit Nose Fuze Mk 30 Mod 3 and a fuze adapter.  It has two spanner holes 180 degrees apart near the base end to facilitate assembly operations.  The fuze adapter is internally threaded to hold Auxiliary Detonator Mk 44 Mod 1, and the Nose Fuze Mk 30 Mod 3 fits over the auxiliary detonator.


5-inch Head Mk 12 and Mods - High Capacity: The 5-inch Head Mk 12 and Mods is 3.125 inches longer than the 5" Mk 10 head used in the 5,000 yard round.  It carries 2/8 pounds more TNT than the Head Mk 10.


5-inch Head Mk 13 and Mods - High Capacity: The 5-inch Head Mk 13 and Mods is 4.78 inches longer than the 5" Head Mk 10.  It also carries about four pounds more TNT.




Motors

5-inch Motor Mk 3 and Mods: The motor tube is a seamless steel tube with internal threads at both ends.  It is machined with a bourrelet ring at each end.  The front closure is a steel disc pressed in position near the front end of the motor tube.  It seals the front end from moisture, dirt, etc., and retains the igniter and propellant grain in place.  A thin felt pad cushions any contact between the front closure and the igniter.  The Igniter Mk 17 Mod 0 consists of a flat tin case containing 35 grams of black powder and an electric squib.  A felt disc one inch thick protects the grain from accidental shock.  It has an eccentrically placed hole which houses and forms a snug fit for the igniter case.

The propellant is an inhibited, cruciform grain weighing approximately ten pounds.  The nozzle plate assembly consists of eight nozzles and a grid mounted on a nozzle plate.  The cylindrical T-shaped steel grid is pressed into place and peened in position in a center hole in the nozzle plate.  It acts as a spacer between the grain and the nozzle plate, creating a chamber which equalizes the pressure to all nozzles during burning.  The nozzles are press fitted into the plate and are canted 12 degrees to give a clockwise rotation.  The nozzle-plate ring assembly consists of a nozzle-plate ring and the insulated contact ring.  The contact ring is a steel band around the nozzle-plate ring and is insulated from it.  The plate ring and contact ring are the two terminals of the ignited electrical circuit.  The rings are short circuited by a band.  The short-circuiting band must be removed when preparing the rocket for firing.  The rear closure is a thin aluminum cup cemented in place in the after end of the motor, and blows out after the motor pressure builds up.


5-inch Motor Mk 4 and Mods: The 5-inch Rocket Motor Mk 4 is similar to the Mk 3 discussed above, except that the motor tube is seven inches shorter than the Motor Mk 3.  The Igniter Mk 18 with shorter leads is used.  Propellant Grain Mk 22 Mod 0, shorter and weighing approximately 5.5 pounds, is used.  The nozzle in the nozzle-plate assembly has a smaller throat diameter.


5-inch Motor Mk 5 Mod 1: The Mk 5 Mod 1 is similar to the Mk 4, except that it is 3.125 inches shorter and the nozzle plate has four instead of eight nozzles.  This shorter motor gives a range of 2,500 yards and a maximum velocity of 475 feet per second, which is suitable for barrage purposes.


5-inch Motor Mk 6 Mod 0: The Mk 6 Mod 0 is also similar to the Mk 4 and Mods, except that it is 4.78 inches shorter and the nozzle plate has only four nozzles.  The cant of these nozzles has been increased to insure stable flight of the round at slower velocities.  This shorter motor gives a range of 1,250 yards and a maximum velocity of 340 feet per second, which is suitable for barrage purposes.

Next Time: Navy Rockets (Part 4)

American Projectiles and Explosives - Navy Rockets (Part 2)

American Projectiles and Explosives

Navy Rockets






3.5-inch Window

Overall length: 45.1 inches (approx.)

Weight: 32 pounds

Head length: 23.2 inches

Head weight: 14.25 pounds (loaded)

Motor length: 23 inches

Motor diameter: 3.25 inches

Width of tail fins: 9.2 inches

Length of tail fins: 8 inches

Fuze: Base Fuze Mk 134

General: The window rocket is designed to be fire from Naval vessels equipped with a modification of the present shipboard launcher.  The round carries a payload of paper-coated metal foil strips which are scattered in the air by a delayed-action charge.  The payload is ejected at an altitude of 1,200 feet and range of 2,000 yards at 40 degrees of elevation.


Description: The window rocket consists of a 3.5-inch Rocket Head Mk 10, Mk 14 Mod 0, or Mk 15 Mod 0 and a 3.25-inch Rocket Motor Mk 12 Mod 0, Mk 14 Mod 0, or Mk 14 Mod 1.  The motor uses the propellent grain Mk 7 Mod 1, weighing 2.8 pounds.


The rocket head contains a 3.5-inch rocket-head load - Mk 2, Mk 3, Mk 4, Mk 5, or Mk 8 - which is housed in a split steel ejection liner.  It has a closure adapter on the after end, an obturator cup for sealing the front end, and a solid wood ogive cap retained by three aluminum rivets in the Mk 10, hollow-steel friction fit in the Mk 14 and Mk 15.  The closure adapter, which is welded to the after end, carries a copper diaphragm plate with a firing pin, and also serves as a chamber for the Cal. 32 blank cartridge which ignites the fuze.  The Fuze Mk 134 consists of a plastic case containing a length of Ensign Bickford fuze and a 20-gram ejector charge of black powder.

All strips are 3/16 inches wide and 0.008 inches thick except the Mk 9, which are 1/2 inch wide.



Operation: When the rocket is fired, gas pressure blows out the forward closure disc of the motor and exerts force on the diaphragm plate in the base of the motor adapter.  The diaphragm collapses, and the firing pin is forced into the primer, firing the blank cartridge. The flash from the cartridge ignites the fuze, which burns for 15 seconds and then ignites the black powder ejection charge.  The firing of the ejector charge forces off the ogive cap and pushes the load forward out of the head.  The strips are then dispersed.


Remarks: The Motors Mk 12 Mod 0 and Mk 14 Mod 0 carry adjustable lug bands; the lugs are welded to the Motor Mk 14 Mod 1.  The Mk 14 Mod 0 and Mk 14 Mod 1 have a metal base cap during shipping, to protect the electrical connector.

The head Mk 15 Mod 0 is one inch longer than the Head Mk 14 Mod 0

3.5-inch Flare

Overall length: 47 inches (approx.)

Weight: 33.5 pounds

Head length: 23 inches

Head weight: 16.5 pound

Motor length: 24.5 inches

Motor diameter: 3.25 inches

Fuze (Head Mk 14): Base Fuze Mk 134

Fuze (Head Mk 15): Base Fuze Mk 128

General: The 3.5-inch rocket flare was developed for use from surface ships, particularly motor torpedo boats.  The illuminant candle produces an average of 800,000 candle power for approximately twenty-nine seconds.  The rocket motor carries the flare out 1,800 yards before ignition.

The flare consists of the following major components: 3.25-inch Motor Mk 12 Mod 0, Mk 14 Mod 0, or Mk 14 Mod 1; 3.5-inch Head Mk 10 Mod 0, Mk 14 Mod 0, or Mk 15 Mod 0; and Body Load (Flare) Mk 7 Mod 0.


Head: All the heads are interchangeable and differ only in minor details.  The 3.5-inch Head Mk 10 Mod 0 has a wooden nose piece held in place by three shear pins, while the Mk 14 Mod 0 and Mk 15 Mod 0 have a sheet-metal nose piece press-fitted in place.  The Mk 15 Mod 0 is one inch longer than the other two.

The head consists of a 3.25-inch seamless steel tube which incorporates a 3.5-inch diameter closure adapter welded to the after end.  This closure adapter carries a copper diaphragm plate with a firing pin, and serves as a chamber for the caliber .32 blank cartridge which ignites the fuze.  The balance of the head is taken up by the candle and parachute from the 4-inch illuminating projectile, the composition of the candle slightly changed to increase the candle power in the shorter burning time.

Motors: The three motors are similar and interchangeable.  The principal distinguishing feature of the 3.25-inch Motor Mk 14 Mod 1 is the use of welded-on launcher lugs replacing the lug bands employed on the earlier models.  The motor housing is a 3.25-inch seamless steel tube containing a forward closure disc, Igniter Mk 11 Mod 0, Tubular Ballistite Grain Mk 7 Mod 1 (2.8 pounds), steel grid, welded nozzle, and pigtail.  Four tail fins, three inches by eight inches, are mounted on a sleeve fixed to the after end.  A thread projector on the forward end and shipping cover taped on the after end protect the motor in shipment.  The 3.25-inch Motor Mk 12 Mod 0 does not have a shipping cover on the after end.



3.5-inch and 5-inch A.R. with 3.25-inch Motors

General: The 3.5-inch rockets were designed to be used against smaller targets, such as submarines and tanks.  For larger targets, the 5-inch rocket was developed from the 5-inch anti-aircraft shell.  The 3.5-inch Solid Head Mk 8 and the 3.5-inch F.S. and P.W.P. Smoke-filled Heads Mk 6 are the only ones now being issued.  The 3.5-inch H.E. heads were replaced by the 5-inch heads.  The former were never issued, because of the small load of TNT carried, as compared to the 5-inch heads.


Heads


3.5-inch Mks 1 and 2: The head is of solid steel and contains no high explosive or fuze.  The shape of the round gives a relatively long underwater travel at shallow depth-of-entry angles (about 20 degrees), and it is used as a semi-armor-piercing projectile against submarines or tanks.  The Mk 1 was the California Institute of Technology production which was adopted by Bureau of Ordnance and designated the Mk 2.


3.5-inch Mks 3 and 5: The head is filled with TNT and fitted with an adapter in the nose to take the Fuze Mk 149.  With a second adapter, the diameter is reduced to 1.5 inches to take the Fuze Mk 148.  These rounds were not issued and were replaced by the 5-inch heads, which contain a greater load of high explosive.


3.5-inch Mk 4: The head has a semi-armor-piercing nose and is filled with TNT.  This round was not issued, because of the small load of high explosive, and was replaced by the 5-inch heads.

 

3.5-inch Mks 6 and 9: The head is filled with F.S. or P.W.P. smoke.  The Mk 9, the initial California Institute of Technology production, was not issued.  The Bureau of Ordnance, in adopting this head, increased the length 1-1/2 inches and issued the round as the Mk 6.

3.5-inch Mk 8: The head is of solid steel and contains no high explosive or fuze.  The round was developed to give better underwater travel and replaces the 3.5-inch Head Mk 2.


5-inch Mk 1 Mod 0: The head is filled with TNT and weighs 46.5 pounds when fitted with a Fuze Mk 143.  The same adapter rings are used as on the 3.5-inch Head Mk 5.  The head is issued with a nose plug.  The nose fuze must always be assembled in the head before firing.  Fire with the fuze on "safe" if delay is desired.  The head is shipped with the base fuze sealed in place.  This base fuze must not be removed.


5-inch Mk 1 Mod 1: This head differs from the 5-inch Head Mk 1 Mod 0 only in that the nose is especially cavitated to take the Fuze Mk 172 Mod 0, which is larger than the Mk 149 or other nose fuzes and therefore is not interchangeable with them.




Motors


The 3.25-inch Motor Mk 7 is used with the 3.5- and 5-inch heads described above.  At the forward end of the motor are a black-powder igniter and an electric squib.  Two electric leads extend through the motor and out the after end to a cable and plug connection.  At the after end of the motor, there are a nozzle and a bag of silica gel which acts as a dehydrating agent in keeping moisture from the ballistite grain.  The grain used in the cruciform type with inhibitors, 33 inches long, 2.75 inches in diameter, and weighing 8.5 pounds.

The tail consists of four sheet-metal fins set 90 degrees apart and welded to a central cylinder.  The tail is slipped over the after end of the motor and is secured by a tail locking ring, which screws on.


Remarks: The 3.5-inch (H.E. and F.S.) have a maximum velocity of 1,200 feet/sec exclusive of plane speed, as compared to 800 feet/sec for the 5-inch H.E.

The 3.5-inch Heads Mk 11, incendiary, and Mk 12, gas, were never loaded.

Next Time: Navy Rockets (Part 3)

American Projectiles and Explosives - Rocket Projectiles

American Projectiles and Explosives

Army Rockets

2.36-inch A/T

Service: M6A1, M6A3, M6A4, M6A5

Practice: M7A1, M7A3, M7A4, M7A6

  

M6A1 and M6A3 Data

Overall length: 21.6 inches
Total weight: M6A1 - 3.4 pounds; M6A3 - 19.4 pounds
Head length: 8.6 inches
Body length: 4.11 inches
Body diameter: 2.23 inches
Body wall thickness: 0.087 inches

Ogive length:
-M6A3 (Cone-Shaped): 4.5 inches
-M6A3 (Hemispherical): 4.56 inches

Ogive diameter (at flange): 2.245 inches
Motor tube length: 6.32 inches
Motor tube (inner diameter): 1.06 inches
Motor tube wall thickness: 0.095 inches

Maximum range: 700 yards
Effective range: 300 yards
Muzzle velocity: 265 feet/sec

Color: Olive drab

Explosive: Pentolite


General: Pill boxes, tanks, and armored vehicles are prime targets.  The rocket can also be used in a stationary emplacement for demolition or as an anti-tank mine or a booby trap.  The rocket can penetrate three inches of homogeneous steel armor plate at all ranges and at angles of impact as low as 30 degrees, employing the shaped-charge explosive.


Launcher: The Rocket Launcher M1A1, commonly called the "bazooka", is an electrically operated weapon of the open-tube type, fired from the shoulder, and weighing 13.26 pounds.  Rocket Launcher M9A1 is similar but breaks down into two sections, each 31 inches long, for ease in transporting.


Construction: The 2.36-inch A/T Rockets M6A1 and M6A3 are identical except for difference in the ogive and the tail assembly.  In other respects the two rockets are similar, consisting of a hollow ogive crimped onto the body, a body union fitting into the base of the body with internal threads to receive the motor, and a fuze which is located in the forward end of the motor tube.  The M6A1 has a conical ogive, whereas the M6A3 has a hemispherical ogive which gives better penetration by forming a stronger stand-off piece for the shaped-charged effect of the explosive.  M6A4 is like the M6A3, except that it is lighter, being made of high-strength alloys, and also uses the Bore-Safe Fuze M400.  The M6A5 uses the Bore-Safe Fuze M401 and has a larger propellant grain, which eliminates the safety disk.


Tail Assembly:  The M6A1 has six fins (5 and 1/2 inches long) spot-welded to the nozzle, a steel cup internally threaded at the forward end to screw onto the motor tube.  The M6A3 has a different type of tail assembly to obtain fin area and counteract the change of the center of gravity effected by the hemispherical nose.  This tail assembly consists of four sheet-steel fins 2 and 5/16 inches long, each of which is curved over an arc of 90 degrees on its outboard edge to form a blade.  Each fin is joined to the other by welding, with an overlap of approximately a 1/2 inch to form a circular drum which is actually nothing more than a continuation of the four fins.  The bases of the fins are spot-welded to the nozzle.  In the M6A5 and M7A6 the free end of the ignition wire is attached to the shroud tail by a chip-board disk, instead of the tape on earlier models.


Propellant: The propellant consists of five sticks of ballistite.  On an average, the propellant weighs approximately 61 and 1/2 grams, though it is loaded not by weight but rather by length of powder stick, to keep the pressure for various rounds at a relatively constant value.  The M6A4 and M6A5 use the Powder M7, which burns at a lower temperature, +120 to -40 degrees Fahrenheit.


Fuze: The fuze for the M6A1 and M6A3 consists of a steel firing pin which slips into the central cavity of the fuze body, where it is held in a rearward position by the firing pin spring.  A circumferential groove midway down the length of the firing pin receives the safety pin, which extends through the motor tube.  When the safety pin is removed, the firing pin is free to move forward, restrained only by the action of the firing pin spring.  After the safety pin has been removed, the firing pin will overcome the spring and detonate the rocket if it is dropped over four feet.  The fuze body contains the Detonator M18 of lead azide and tetryl, and the booster charge of tetryl.


Remarks: The practice rounds are similar to their accompanying service rounds, except that they are inert-loaded and have a dummy fuze or steel weight to fill the empty fuze space.

The M6A5 and M7A6 have plastic closing plugs, making them waterproof rounds.  They also use the Powder M7, which burns at a lower temperature, +120 to -40 degrees Faherenheit.

The M6A1 and M7A1 are now considered obsolete.









2.36-inch Smoke (W.P.) M10, M10A1, M10A2, M10A3

M10 Data

Overall length: 17.1 inches
Total weight: 3.4 pounds
Head length: 5 and 1/2 inches
Head diameter: 2.3 inches
Maximum diameter: 2.36 inches

W.P. charge: 405 grams
Burster charge: 4 grams
Effective range: 300 yards

Color:
-Motor: Olive drab
-Head: Blue grey



General: This rocket is designed not only as a screening agent, but also to cause casualties.  White phosphorus in smoke form has little effect upon the human body, but particles cause small burns.  This rocket makes an effective weapon for dislodging enemy troops from dug-outs and foxholes.


Launcher: The 2.36-inch Smoke Rocket M10 is fired from the Launcher M1A1 or M9, the "bazooka".


Construction: The components of this rocket are the motor and the head assembly.  The motor presently used is the M6A1, which is being replaced by the M6A3.  As new motors are developed, it is contemplated that this rocket will be modified.

The head assembly consists of a container for the smoke charge with a long burster well containing PETN inserted from its after end.  A collar is soldered to the base of the container.  The spacer slips over the threads of the collar and is held against the flat surfaces of the collar by the fuze body, forming a joint between the two.  The primer holder is threaded into the fuze body.


Tail Assembly:  The 2.36-inch Smoke Rocket M10 has the standard tail assembly for this M6A1 or M6A3 motors.


Fuze: The fuze is similar to that used in the A/T Rocket M6A3.


Remarks: The M10A1 and M10A2 differ from the M10 in the type of propellant used.  The M10A1 used the T1E1 Salted Powder, with a temperature range of 120 to -20 degrees Fahrenheit.  The M10A2 uses the Powder M7, 120 to -40 degrees Fahrenheit.  The M10A3 differs from the M10A2 in that it uses the Fuze M401.










3.25-inch Target M2, M2A1, M2A2

Overall length: 59 inches
Width across fins: 24 inches
Weight: 37.5 pounds
Propellant weight: 3.2 inches

Range: 1,700 yards
Maximum velocity: 530 feet/sec
Burning time of flare: 30 seconds


General: This is a high-speed target for firing practice with automatic A.A. weapons.


Propellant: The propellant has grains five inches long and 7/8-inch in diameter, with a 5/16-inch axial hole.  It is ignited by an electric squib.


M2A1: When a flare is added to the 3.25-inch Target Rocket M2 for anti-aircraft target practice at night, the resulting projectile is designated as the M2A1.  The flare burns for 30 seconds from the beginning of flight.


M2A2: This design has a flat nose, to which is threaded a yellow flare for both day and night tracking.  It also has a different system for igniter contact: the lead wires pass in turn through the nozzle and an inner fiber closing cup and connect to a household-type service plug, which is held by an outer fiber-board closing cup.  There are 18 inches of igniter cable coiled between the closing cups, to allow ample lead for connecting to the launcher.








4.5-inch H.E. M8, M8A1, M8A2, and M8A3; also Practice M9, M9A1, M9A2, and M9A3

Overall length: 33 inches
Total weight: 38 pounds
Head length: 7.5 inches
Wall thickness: 0.2 inches

Burster tube length: 15.5 inches
Fin length: 4 and 1/3 inches
Bursting charge weight (TNT): 4.3 pounds
Maximum range: 4,500 yards
Muzzle velocity: 840 feet/sec

Fuzing: M4, M4A1, M4A2


General: The initial issue of the rocket went to the Army Air Forces for projection from aircraft launchers against ground targets; but, in-asmuch as the rocket was originally designed for use from ground launchers, its use in aircraft has been discontinued.


Construction: The head is a thin-walled high-capacity type, rounded at the nose to form the ogive, threaded at the nose to take the fuze adapter, and threaded externally aft to fit into the motor.  A burster tube is fitted to the head and extends down into the motor, a design which utilizes the motor tube for additional fragments, since the burster tube as well as the head itself is loaded with TNT.

The motor is a steel tube of uniform diameter except at the after end, where it constricts and then flares to form the nozzle.  The motor houses the trap assembly, which consists of ten wires running from the trap plate on the forward end to the trap ring on the after end.  The trap assembly holds the thirty sticks of propellant and fits around the burster tube.  The motor tube is threaded internally forward to take the head, and just abaft this thread is a groove which weakens the tube to provide a safety shear point, should the motor pressure become too great.

The fin assembly for the rocket opens and guides the rocket in flight only after the rocket has cleared the launcher.  The fins of the assembly are held in place by the fin retainer, which is expelled by the blast of the escaping gas.  After clearing the launcher, the fins snap to their outstretched position.  There are six fins.

The M8A1 involved a change in the design of the motor tube to strengthen it on the threaded end.  The head of the M8 was used by machining new base threads.  Tests on the M8A1 indicated that the base of the modified head was weak, and a new head was designed for use with the motor of the M8A1.  This rocket, the M8A2, will suspersede the M8 and M8A1.  The M8A3 is a modification of the M8A2 made by the addition of a locking burr to each fin blade to assist in rigidly maintaining the fin in full open position during flight.


Propellant: The propellant consists of 30 sticks of ballistite.  Each stick is five inches long and 7/8-inch in diameter with a 1/4-inch axial hole.  Three sticks are placed on each trap wire, and there is sufficient clearance between the sticks and the wire to allow burning of the inner stick wall simultaneously with the burning of the outer wall.  Two igniter-bag assemblies are bound on two opposite columns of the propellant.  The bags assist the ignition of the propellant by catching the flame of the igniter and, in turn, igniting the upper propellant sticks.


Practice Rockets M9, M9A1, M9A2, M9A3: These rockets are similar in design and construction to the M8 series, lacking only the explosive charge and live fuze.  The Fuze M4 and booster may be assembled and used in the M9 as a spotting charge.









4.5-inch H.E. S.S. M16, M16E1, and M16E2; Practice M17, M17E1, and M17E2; M20 and M21

M16 Data

Overall length: 31 inches
Total weight: 42.5 pounds
Head length (w/ burster tube): 23.29 inches


TNT charge: 4.3 pounds
Maximum range: 5,250 yards
Muzzle velocity: 830 feet/sec

Fuzing: M81


Description: The head, loaded with high explosive, contains a fuze-well cup and a burster tube.  The burster tube projects about 15 inches into the center of the rocket motor to secure additional fragmentation.  The motor body is a steel tube threaded at each end to receive the head and the nozzle plate, which contains eight nozzles equally spaced in a circle and one nozzle in the center.  The eight nozzles are set at an angle in order to impart rotation to the round when fired.  The center nozzle is normally closed by a blowout disc which is designed to fail when the internal pressure in the body surpasses a predetermined limit.  The nozzle openings are protected by a plastic sealing disc which remains in place during firing and is blown out by the rocket blast.


Propellant: The propelling charge consists of 30 grains of ballistite strung on wires of a cage-like trap.  The igniter consists of a charge of black powder enclosed in a plastic tube attached to the trap and running the length of the charge.  The tube also contains an electric squib.  The leads of the squib pass through one of the nozzles, one lead being ground to the motor body and the other connected to a contact ring.


M20: The M20 is similar in design and construction to the M16, differing only in that the ignition wires are attached to spools rather than contact rings.


Practice Rockets M17 and M21: These are similar in design and construction to the H.E. rounds, but lack the explosive charge and the live fuze.

The M16E1 has a deeper fuze cavity for the V.T. Fuze M402 (Mk 173).  Shipped with these rockets is a supplementary charge to fill part of this cavity in case the Fuzes M81 or M48A2 are used.

The M16E2 is like the M16E1, except that purge pellets of 411E composition have been added to eliminate chunks in burning.








5-inch A.R.

No picture available

The Army is currently using the Navy-designed 5-inch aircraft rockets.

7.2-inch Chemical M25 and M27

No picture available

In the 7.2-inch size, the Army has standardized the chemical round designed by the Navy.

Next Time: Army Developmental Types

American Projectiles and Explosives - 5-inch Projectiles (Part 3)

American Projectiles and Explosives

5-inch Projectiles





5-inch Illuminating Mk 44 Mod 1

No picture available

Guns used in: 5"/38
Overall length w/ nose fuze: 19.97 inches
Overall length w/o nose fuze: 16.465 inches
Diameter of base: 4.973 inches
Distance base to band: 2.43 inches
Width of band: 2.25 inches
Diameter at bourrelet: 4.985 inches

Filling: Black Powder expelling charge; magnesium flare
Weight of filling: 2.5 ounces - expelling charge
Weight of loaded projectile: 54.5 pounds
Charge/Weight ratio: N/A

Cartridge case: Mk 5
Primer: Mk 13 and all Mods
Tracer: N/A

Fuzes: Mk 18 Mods 2, 3, and 4
-Mk 50 Mods 0-4
-Mk 63 Mod 0


This projectile is currently assembled with the Illuminating Contents Mk 4 Mod 5





5-inch Illuminating and 5-inch W.P. Mk 45 Mod 0

No picture available

Guns used in: 5"/25
Overall length w/ nose fuze: 19.97 inches
Overall length w/o nose fuze: 16.465 inches
Diameter of base: 4.968 inches
Distance base to band: 1.98 inches
Width of band: 2 inches
Diameter at bourrelet: 4.985 inches

Filling: Black Powder expelling charge; magnesium flare
Weight of filling: 2.5 ounces - expelling charge
Weight of loaded projectile: 54.5 pounds
Charge/Weight ratio: N/A

Cartridge case: Mk 4, Mk 4 Mod 2
Primer: Mk 13 and all Mods
Tracer: N/A

Fuzes: Mk 18 Mods 2, 3, and 4
-Mk 50 Mods 0-4
-Mk 63 Mod 0


This projectile is currently assembled with the Illuminating Contents Mk 4 Mod 5.

The W.P. projectile uses the body of the Mk 45 and the incendiary contents of the W.P. shell.





5-inch Illuminating  Mk 48 Mod 0

Guns used in: 5"/54
Overall length: 26 inches
Overall length w/o nose fuze: 22.28 inches
Diameter of base: 4.973 inches
Diameter at bourrelet: 4.985 inches

Filling: Black Powder expelling charge; magnesium flare
Weight of filling: 2.5 ounces - expelling charge
Weight of loaded projectile: 70 pounds
Charge/Weight ratio: N/A

Cartridge case: Mk 6
Primer: Mk 13 and all Mods
Tracer: N/A

Fuzes: Mk 25 Mod 1


The Illuminating Contents Mk 4 Mod 5 are used, modified for a lengthened spacer sleeve.

The projectile is identical in all respects to the Mk 48, except that it has a double rotating band.






5-inch Window Projectile

Guns used in: 5"/38
Overall length w/ nose fuze: 20 inches
Overall length w/o nose fuze: 15.8 inches
Diameter of base: 4.968 inches
Distance base to band: 2.43 inches
Width of band: 2.25 inches
Diameter at bourrelet: 4.985 inches

Filling: Black Powder expelling charge; magnesium flare
Weight of filling: 2.5 ounces - expelling charge

Weight of loaded projectile:
-Load Mk 1 Mod 1: 53.9 pounds (approx.)
-Load Mk 2 Mod 0: 54.6 pounds (approx.)
-Load Mk 4 Mod 0: 53 pounds (approx.)

Charge/Weight ratio: N/A

Cartridge case: Mk 5
Primer: Mk 13 and all Mods
Tracer: N/A

Fuzes: Mk 18 Mods 2, 3, and 4
-Mk 50 and all Mods
-Mk 63 Mod 0

Projectile Body:
-5-inch Ill. Mk 30 Mods 5, 7, and 9
-5-inch Ill. Mk 44 Mod 1


Window Load Mk 1 Mod 1: Consists of about 13,800 aluminum foil strips, each 8 inches long, 3/16 inches wide, and 0.00035 inches thick, backed on either side by 12 pounds of tissue paper, solid glued.  The strips are stacked within a four-section cylindrical wood form, which is encased in a split steel sleeve, the whole inserted into the projectile cavity.

Window Load Mk 2 Mod 0:  Consists of 19 rolls of aluminum foil stacked within a split steel sleeve.  Each roll contains continuous foil 600 feet long, 1/2 inch wide, and 0.0009 inches thick.  One end of the foil is attached to a cardboard disc by a rayon leader 15 feet long, insuring streaming out of the foil roll.  The foil rolls, with their cardboard discs, are each encased in a split retainer ring, forming a load unit.  The units are separated by aluminum discs when loaded in the split steel sleeve.

Window Load Mk 4 Mod 0:  Consists of two stacks of 13,800 aluminum foil strips, each stack separated by an aluminum disc.  Each strip is 5.1 inches long by 3/16 inches wide.  The strips are stacked within two four-section cylindrical magnesium forms, which are encased in a split steel sleeve.


Operation:  The explosion of the black powder ejection charge, initiated by the fuze, exerts a pressure against the baffle plate and forces the split steel sleeve, window load, and base plug out of the base end of the projectile.






5-inch White Phosphorus Smoke Projectile

Guns used in: 5"/38
Overall length w/ nose fuze: 20 inches
Overall length w/o nose fuze: 15.8 inches
Diameter of base: 4.968 inches
Distance base to band: 2.43 inches
Width of band: 2.25 inches
Diameter at bourrelet: 4.985 inches

Filling: Black Powder expelling charge; magnesium flare
Weight of filling: 2.5 ounces - expelling charge
Weight of loaded projectile: 53 pounds
Charge/Weight ratio: N/A

Cartridge case: Mk 5
Primer: Mk 13 and all Mods
Tracer: N/A

Fuzes: Mk 63 Mod 0 (M.T.F)
-Mk 18 Mods 2, 3, and 4 (M.T.F.)
-Mk 50 and Mods (M.T.F.)
-Mk 29 Mod 3 (P.D.F.)
-Mk 66 Mod 0 (P.D.F.)
-Mk 61 Mod 0 (M.T.F.) -for use with 1,200 f/s initial velocity reduced charge-


Projectile Body: 5-inch Illuminating Mk 30 Mods 1-8

The projectile body, base plate, and expelling charge are the same as those for the 5-inch Illuminating Projectile Mk 30.

The canister holding the W.P. filled tubes is of 0.03-inch thick sheet steel and measures 12.03 inches long by 3.9 inches in diameter.  It is painted olive drab overall.  Through the center of the canister is inserted a burster tube containing the ballistite burster charge, with a black powder delay fitted to the upper end of the tube.  The canister is divided into four sections internally, with each section containing 42 W.P. filled steel tubes 0.5 inches in diameter and 2.86 inches long, 168 tubes in all.  The canister is filled through the base with molten W.P. and closed with two 1/2-inch pipe plugs.


Type of Filling
Expelling charge --- 2 ounces black powder
Bursting charge --- 14 grams Ballistite
Smoke filling --- 7.06 pounds white phosphorus


The black powder expelling charge, ignited by the fuze, initiates the delay element at the upper end of the burster tube and forces off the base plate, ejecting the canister rearward.  The delay initiates the burster, which ruptures the canister and scatters the W.P. filled steel tubes.  The smoke cloud thus formed is about 30-40 yards in diameter.  The projectile combines screening, anti-personnel, and slight incendiary effect.

Next Time: 6-inch Projectiles (Part 1)

American Projectiles and Explosives - 5-inch Projectiles (Part 2)

American Projectiles and Explosives

5-inch Projectiles





5-inch A.A. Common Mk 28 Mod 9 (Obsolete)

Guns used in: 5"/25
Overall length w/ nose fuze: 20.7 inches
Overall length w/o nose fuze: 16.945 inches
Diameter of base: 4.973 inches
Distance base to band: 2.43 inches
Width of band: 2 inches
Diameter at bourrelet: 4.985 inches

Filling: Explosive D, Composition A
Weight of filling: 7.33 pounds
Weight of loaded projectile: 51.7 pounds
Charge/Weight ratio: 14%

Cartridge case: Mk 4
Primer: Mk 13 and all Mods
Tracer: None
Fuzes: Mk 32 all Mods (V.T.F.); Mk 40 all Mods (V.T.F.)

Auxiliary Detonating Fuze:
-Mk 17 and Mods
-Mk 46 Mod 0
-Mk 54 Mod 0

This projectile is fuzed with V.T. fuzes only.  The projectile adapter is removed, and a gas-checked base plug is inserted.  No tracer or base fuze is used with this projectile.

The Fuze Mk 40 and Mods is currently replacing the Mk 32 and Mods in all assemblies.  The Auxiliary Detonating Fuze Mk 54 is replacing the Fuzes Mk 17 and Mk 46 in all assemblies.

This round is also issued B.L. & P. or B.L. & T. with the Tracer Mk 6 and adapter, or a cut-off Base Fuze Mk 13 for target practice.





5-inch A.A. Common Mk 31 Mods 1 - 11

No picture available

Guns used in: 5"/38
Overall length w/ nose fuze: 20.7 inches
Overall length w/o nose fuze: 16.625 inches
Diameter of base: 4.97 inches
Distance base to band: 2.43 inches
Width of band: 2.25 inches
Diameter at bourrelet: 4.985 inches

Filling: Explosive D, Composition A
Weight of filling: 7.25 pounds
Weight of loaded projectile: 55.12 pounds
Charge/Weight ratio: 13.33%

Cartridge case: Mk 5
Primer: Mk 13 and all Mods
Tracer: None
Fuzes: Mk 32 all Mods (V.T.F.); Mk 40 all Mods (V.T.F.); Mk 53 and all Mods (V.T.F.)

Auxiliary Detonating Fuze:
-Mk 17 and all Mods
-Mk 44 Mod 0 and 1
-Mk 46 Mod 0
-Mk 54 Mod 0 and 1

The Mk 31 projectile was originally designed to receive the Base Fuze Mk 13, which is now obsolete.  The projectile will now be found fitted only with V.T. fuzes and a plug in the base.

The Nose Fuze Mk 40 is replacing the Mk 32 and Mods.  With these fuzes, the projectile adapter will be removed, and the Auxiliary Detonating Fuze Mk 54 will be employed, replacing the previously used Auxiliary Detonating Fuzes Mk 17 and Mk 46.

When the V.T. Fuze Mk 53 is used, the projectile adapter is removed and the Auxiliary Detonating Fuze Mk 44 employed.

This projectile is also issued B.L. & P. or B.L. & T. with the Tracer Mk 6 and adapter, or a cut-off Base Fuze Mk 13 for target practice.





5-inch A.A. Common Mk 34 Mod 10

No picture available

Guns used in: 5"/38
Overall length w/ nose fuze: 20.7 inches
Overall length w/o nose fuze: 17.2 inches
Diameter of base: 4.97 inches
Distance base to band: 2.43 inches
Width of band: 2.25 inches
Diameter at bourrelet: 4.985 inches

Filling: Explosive D, Composition A
Weight of filling: 7.25 pounds
Weight of loaded projectile: 55.18 pounds
Charge/Weight ratio: 13.33%

Cartridge case: Mk 5
Primer: Mk 13 and all Mods
Tracer: Mk 9

Fuzes:
-Base: Mk 28 and all Mods

-Nose: Mk 18 Mods 2, 3, and 4 (M.T.F.)
-Mk 50 Mods 0-4 (M.T.F.)
-Mk 29 Mods 2 and 3 (P.D.F.)
-Mk 32 and all Mods (V.T.F.)
-Mk 40 and all Mods (V.T.F.)
-Mk 64 Mod 0 (M.T.F.)


Auxiliary Detonating Fuze:
-Mk 17 and all Mods
-Mk 46 Mod 0
-Mk 54 Mod 0 and 1

This projectile consists of a Projectile Mk 31 Mo d10 modified to receive a Base Fuze Mk 28.  The Auxiliary Detonating Fuze Mk 54 is replacing the Auxiliary Detonating Fuze Mk 17 and Mk 46 in all assemblies.

The V.T. Fuze Mk 40 and its Mods are replacing the Mk 32 and Mods.  When these fuzes are used in this projectile, no base fuze or tracer is employed.  The projectile adapter is removed, and a gas-checked fuze-hole plug is fitted in the base.






5-inch A.A. Common Mk 35 Mods 1-12

Guns used in: 5"/38 (case), 5"/51 (bag)
Overall length w/ nose fuze: 20.7 inches
Overall length w/o nose fuze: 17.225 inches
Diameter of base: 4.973 inches
Distance base to band: 2.43 inches
Width of band: 2.25 inches
Diameter at bourrelet: 4.985 inches

Filling: Explosive D, Composition A
Weight of filling: 7.25 pounds
Weight of loaded projectile: 55.18 pounds
Charge/Weight ratio: 13.1%

Cartridge case: Mk 5
Primer: Mk 13 and all Mods
Tracer: Mk 9

Fuzes:
-Base: Mk 28 and all Mods

-Nose: Mk 18 Mods 2, 3, and 4 (M.T.F.)
-Mk 50 and all Mods (M.T.F.)
-Mk 61 Mod 0 (M.T.F.)
-Mk 29 Mods 2 and 3 (P.D.F.)
-Mk 32 and all Mods (V.T.F.)
-Mk 40 and all Mods (V.T.F.)
-Mk 53 and all Mods (V.T.F.)
-Mk 63 Mod 0 (M.T.F.)


Auxiliary Detonating Fuze:
-Mk 17 and all Mods
-Mk 44 Mods 0 and 1
-Mk 46 Mod 0
-Mk 54 Mod 0 and 1

The Nose Fuze Mk 40 is replacing the Mk 32 when used in the 5"/38 gun.  With the 5"/51 bag gun, however, Nose Fuze Mk 32 Mod 40, rather than the Nose Fuze Mk 40, is employed.  When these fuzes are used, the projectile adapter is removed, a gas-checked base fuze plug, with no tracer, is fitted into the base, and the Auxiliary Detonating Fuze Mk 54 is employed.

When the V.T. Fuze Mk 53 is used, the base is fitted with a gas-checked base-fuze plug, with no tracer, the projectile adapter is removed and the Auxiliary Detonating Fuze Mk 44 is employed.

The Auxiliary Detonating Fuze Mk 54 is replacing the Fuzes Mk 17 and Mk 46 in all assemblies.

With the 1200 f/s I.V. reduced charge for the 5"/38 gun, Nose Fuzes Mk 61 and Mk 29 Mods 2 and 3 with the Auxiliary Detonating Fuze Mk 54 will be employed.

All Mods of this projectile, except Mod 6, may be issued B.L. & P. or B.L. & T. with the Tracer Mk 9 and adapter for target practice.

When these projectiles are used in the 5"/51 bag gun, the Primer Mk 15 Mod 1 is used.







5-inch Common Mk 36 Mods 1-4

No picture available

Guns used in: 5"/25
Overall length w/ nose fuze: 20.7 inches
Overall length w/o nose fuze: 17.225 inches
Diameter of base: 4.973 inches
Distance base to band: 2.43 inches
Width of band: 2 inches
Diameter at bourrelet: 4.985 inches

Filling: Explosive D, Composition A
Weight of filling: 7.25 pounds
Weight of loaded projectile: 53.85 pounds
Charge/Weight ratio: 13.5%

Cartridge case: Mk 4, Mk 4 Mod 2
Primer: Mk 13 and all Mods
Tracer: Mk 9

Fuzes:
-Base: Mk 28 and all Mods

-Nose: Mk 18 Mods 2, 3, and 4 (M.T.F.)
-Mk 50 and all Mods (M.T.F.)
-Mk 29 Mods 1, 2 and 3 (P.D.F.)
-Mk 32 and all Mods (V.T.F.)
-Mk 40 and all Mods (V.T.F.)
-Mk 53 and all Mods (V.T.F.)
-Mk 63 Mod 0 (M.T.F.)

Auxiliary Detonating Fuze:
-Mk 17 and all Mods
-Mk 44 Mods 0 and 1
-Mk 46 Mod 0
-Mk 54 Mod 0


When the V.T. fuzes are used, the projectile adapter is removed, and a gas-checked base-fuze plug, with no tracer, is fitted into the base.  V.T. fuzes are authorized for use in Mods 2 - 4 only of this projectile.

The Auxiliary Detonating Fuze Mk 54 is replacing the Auxiliary Detonating Fuzes Mk 17 and the Mk 46.  The Auxiliary Detonating Fuze Mk 44 is used only in conjunction with the V.T. Fuze Mk 53.

All Mods of the Projectile Mk 36 are authorized for use with A.P. steel nose caps and for designation as "H.C." projectiles.

All Mods of the Projectile Mk 36 may also be issued B.L. & P. or B.L. & T. with the Tracer Mk 9 and adapter for target practice.







5-inch A.A. Common Mk 47 Mods 0 and 1

No picture available

Guns used in: 5"/38
Overall length w/ nose fuze: 20.7 inches
Overall length w/o nose fuze: 52.43 inches (???)
Diameter of base: 4.985 inches
Distance base to band: 1.93 inches
Width of band: 2.25 inches
Diameter at bourrelet: 4.985 inches

Filling: Explosive D
Weight of filling: 7.11 pounds
Weight of loaded projectile: 55.18 pounds
Charge/Weight ratio: 7.7%

Cartridge case: Mk 5
Primer: Mk 13 all Mods
Tracer: Mk 9

Fuzes: Same as Mk 35

The Mod 1 differs from the Mod 0 in that the band seat has different knurling.

Only a few thousand of these A.A. Common Projectiles Mk 47 were made.

The Mk 47 was made to furnish a heavier projectile for some newer light-weight fuzes, hence maintaining a standard ballistic weight.  However, it has been fuzed exactly like the Mk 35 up to the present time.









5-inch Illuminating Mk 25 Mods 1-6 and Mod 2 (Obsolete)

No picture available

Guns used in: 5"/51 (bag or case);  Mod 2: 5"/25 (case)
Overall length w/ nose fuze: 19.975 inches
Overall length w/o nose fuze: 15.865 inches
Diameter of base: 4.948 inches
Distance base to band: 2.43 inches
Width of band: 2 inches
Diameter at bourrelet: 4.985 inches

Filling: Black Powder expelling charge; magnesium flare
Weight of filling: 2.5 ounces - expelling charge
Weight of loaded projectile: 54.5 pounds
Charge/Weight ratio: N/A

Cartridge case: Mk 3;  Mod 2: Mk 4, Mk 4 Mod 3
Primer: Mk 13 and all Mods
Tracer: N/A

Fuzes:
Nose - Mk 18 Mod 2, 3, and 4
-Mk 50 and all Mods
-Mk 63 Mod 0



The Mod 2 projectile, used in the 5"/25 gun, is identical to the Mod 1, except for modification of the rotating band.

When these projectiles are used in the 5"/51 bag gun, the Primer Mk 15 Mod 1 is used, and the Nose Fuzes Mk 50 and Mk 63 may be employed.  Use of the Nose Fuzes Mk 50 and Mk 63 is not authorized with rounds used in the 5"/25 and 5"/51 case guns.

The Illuminating Contents Mk 3 are used with projectiles Mods 1 through 4; projectiles Mods 5 and 6 are assembled with Illuminating Contents Mk 4 Mod 5 when used in the 5"/51 bag gun, Illuminating Contents Mk 3 when used in the 5"/51 case gun.











5-inch Illuminating and 5-inch W.P. Mk 27 Mods 1-10

No picture available

Guns used in: 5"/25
Overall length w/ nose fuze: 20 inches
Overall length w/o nose fuze: 15.8 inches
Diameter of base: 4.968 inches
Distance base to band: 1.93 inches
Width of band: 2 inches
Diameter at bourrelet: 4.985 inches

Filling: Black Powder expelling charge; magnesium flare
Weight of filling: 2.5 ounces - expelling charge

Weight of loaded projectile:
-Mods 1-4: 53.65 pounds
-Mods 5-10: 54.5 pounds

Charge/Weight ratio: N/A

Cartridge case: Mk 4, Mk 4 Mod 2
Primer: Mk 13 and all Mods
Tracer: N/A

Fuzes:
Nose - Mk 18 Mod 2, 3, and 4
-Mk 50 and all Mods
-Mk 63 Mod 0


Mods 1, 2, 3, and 4 have a band diameter of 5.10 inches, and Mods 5, 6, 7, 8, 9, and 10 have a band diameter of 5.12 inches.

The Illuminating Contents Mk 4 Mod 5 are used in this projectile.

The 5-inch W.P. projectile utilizes the Mk 27 body with incendiary contents.











5-inch Illuminating Mk 30 Mods 1-8

Guns used in: 5"/38
Overall length w/ nose fuze: 20 inches
Overall length w/o nose fuze: 15.8 inches
Diameter of base: 4.968 inches
Distance base to band: 2.43 inches
Width of band: 2.25 inches
Diameter at bourrelet: 4.985 inches

Filling: Black Powder expelling charge; magnesium flare
Weight of filling: 2.5 ounces - expelling charge
Weight of loaded projectile: 54.5 pounds
Charge/Weight ratio: N/A

Cartridge case: Mk 5
Primer: Mk 13 and all Mods
Tracer: N/A

Fuzes:
Nose - Mk 18 Mod 2, 3, and 4
-Mk 50 and all Mods
-Mk 63 Mod 0


The Illuminating Contents Mk 4 Mod 5 are used in this projectile.








5-inch Illuminating Mk 43 Mod 0

No picture available

Guns used in: 5"/54
Overall length: 26 inches
Overall length w/o nose fuze: 22.28 inches
Diameter of base: 4.973 inches
Diameter at bourrelet: 4.985 inches

Filling: Black Powder expelling charge; magnesium flare
Weight of filling: 2.5 ounces - expelling charge
Weight of loaded projectile: 70 pounds
Charge/Weight ratio: N/A

Cartridge case: Mk 6
Primer: Mk 13 and all Mods
Tracer: N/A

Fuzes: Nose - Mk 25 Mod 1


The Illuminating Contents Mk 4 Mod 5 are used in this projectile, modified to use a lengthened spacer sleeve.

This projectile is identical to the 5-inch Illuminating Projectile Mk 48, except that the latter has a double rotating band.

Next Time: 5-inch Projectiles (Part 3)