TM 9-1904, Ammunition Inspection Guide

414 Pages·2001·35.16 MB·English

by  War Department

Amoclu)DE
WAR DEPARTMENT TECHNICAL MANUAL
TM 9-1904
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Ammunition Inspection Guide
"2 MARCH 1944
RESTRICTED DISSEMINATION OF RESTRICTED MATTER-
The information contained in restricted documents and the essential char-
acteristics of restricted material may be givento any person known tobe in
the service of the United States and to persons of undoubted loyalty and
discretion who are cooperating in Government work, but will not be com-
municated tothe public ortothepressexcept by authorized military public
relations agencies. (See alsoparagraph 19 b, AR 380-f,29 September 1942.)
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TM 9-1904
WAR DEPARTMENT
Washington 25, D. C.. 2 March 1944 CONTENTS
infTorMmat9i-o1n90a4n,dAmgumiudnaintcieoonfIanllspceoctnicoenrnGeudi.de, is published for the
PAGE
SECTION I. INTRODUCTION
A.U. 300.7 (2 Feb 44)
CHAPTER 1. Ammunition in General . .. .. .... . . .... . . . 5
0.0. 300.7/1365 - 2. Safety . .. .... . . . . .... . .... . . ..... . . . . . 21
SECTION II. INTERPRETATION OF ORDNANCE DRAWINGS;
BY ORDER OF THE SECRETARY OF WAR: USE AND CARE OF MEASURING TOOLS
CHAPTER 1. Information Topics .. . .... . .... . . . . ..... 23
2. Regulations Covering Ordnance Drawings for
G. C. MARSHALL, Ammunition Division Materiel... . . .. ... 33
ChiefofStaff. 3. Use and Care of Measuring Tools ..... . . . 37
SECTION III. EXPLOSIVES
OFFICIAL:
CHAPTER'l. Introduction, Military Explosives. .... . . . .. 66
J. A. ULIO,
--2. Low Explosives . .... .. .. .. .. . . .... . . ... 68
Major General,
-3. High Explosives . .... ...... .. . . .... . . ... 96
The Adjutant General. 4. Explosive Trgins .... . ...... . . . .... . . ... 117
5. Exudation . . . ...... ..... .. .. ... . .... . . 132
DISTRIBUTION: 1Bn 9 (2); IC 9 (2), (10). 6. High-explosiveLoading . ... . ... .... . . .... 135
SECTION IV. CHEMICAL WARFARE AGENTS
(For explanation ofsymbols, see FM 21-6.) CHAPTER 1. Chemical Agents . . . . .... . ..... . . ...... . 158
SECTION V. SMALL ARMS AND TRENCH WARFARE
CHAPTER i. Small-arms Ammunition ... . .... .. .. .... . 179
2. Hand Grenades . . . .... . . ... . . .... . . . . .. 234
3. Antipersonnel Mines and Booby Traps. .... 240
4. Rifle Grenades and Rockets. . . .... . . . .... 253
5. Antitank Mines . . . . ... . . . .. . . .... .. . . . 263
6. Bangalore Torpedo . . .. .. ... ..... . . . .... 270
7. Trench Mortar Ammunition... . . .... . . . . . 272
SECTION VI. ARTILLERY AMMUNITION
CHAPTER 1. Introduction to Artillery Fuzes.... . . . .... . 319
2. 20-mm Ammunition . . . .. .. .. .... . . . . .. . 323
3. 37-mm Ammunition ... . . .... . . . ..... . . . 331
4. Ammunition for 40-mm Gun M1 . .... .. . . . 363
5. Ammunition for 57-mmGuns . . . . .... .. ... . 380
6. 75-mm Gun Ammunition ... . . .... . . . .... . 382
7. 75-mmHowitzer Ammunition . .... . . . . ... 425
8. 3-inch Ammunition . .. . . . . .. . . . .... . . . . . 437
9. Ammunition for 90-mm Guns . . . .. ... . ... . 462
10. Ammunitionfor 105-mm Guns and
Howitzers . . . .. .. . . . ... . . . ... . . .... . . 469
3
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RESTRICTED
TM 9-1904 TM 9-1904
AMMUNITION INSPECTION GUIDE 11 SECTION 1.
PAGE
CHAPTER 11. Ammunition for 4.7-inch AA Guns . . . .... . . 484 INTRODUCTION
12. Ammunition for 4.5-inchGuns .... . . .... . . 486
Ammunition for 155-mm Guns and Chapter 1
Howitzers . .... .... . ... . . .... . . .... . . 490 Ammunition in General
14. Ammunitionfor 240-mm Howitzers . . ..... . 522
15. Ammunition for 14-inch Guns . .. . . .... . .. 529 GENERAL.
SECTION VII. BOMBSFOR AIRCRAFT When venturing into any new field, one finds himself confronted
with many new terms and materials to such anextent that he often
CHAPTER-1. Introduction ....... ..... . .... ........ .. 548
becomes lost in a maze of confusion. It is, therefore, necessary tolay
2. G.P. (General Purpose) Bombs... . . . .... . 564
afoundation of information thatwill aid in interpreting the material
3. Semi-armor-piercing and Armor-piercing
which will follow.-
Bombs . .... .... ..... .... . . .... . . ... 605
4. Depth Bombs . .. . . ....... .. .... . . .... . . 623 It is necessary for the ammunition inspector to have a wide and
5. Fragmentation Bombs...... ... .. .. ..... . . 641 completeknowledge ofall thetypesof ammunition that he will come
6. Chemical Bombs . .... ...... . .... . ..... . 667 in contact with in the line of duty, for he will be called on to pass
judgment as to the safe conduct of various operations. To do this,
7. Incendiary Bombs ... ... . ...... ....... . . 677
8. Practice and Drill Bombs. .... .. .. .... . . . 697 he must know all the facts about the material in question. It might
be wellto pointout that all ammunition isinherently dangerous, for
SECTION VIII. MILITARY PYROTECHNICS
its whole purpose of existence is to destroy or kill, but, if handled
CHWP-T-sx-~.1-^Pyrotec mcs . .... . ... . . .... . . .... . . ... "°9 f'W'1y;vftc:.=d:___A erg~frs'i"~ ap " eL r:rt, :f 41" atl
SECTION IX. DESTRUCTION OF UNUSABLE AMMUNITION times, however, it must be given the fullest respect. A great portion
AND EXPLOSIVES ofthe accidents which dooccurcan be traced to some form ofcare-
CHAPTER 1. Introduction . . ... . ... . .... . . .... . . .... . 748 lessness when thefull measureofsafety wasnotapplied.
2. Destruction byDetonation ... . . ... . . .... . 752 Nomenclature. In his ¢wily dutielorthe ammunition inspector will
3. Destruction byBurning . . ..... . . .... .. ... 772 be called upon to discuss ammunition. Whether this discussion be
4. Dumping at Sea... .... . ..... . . .... . . ... 777 written or oral, the proper use of terms or proper nomenclature is
SECTION X. MAGAZINE AREA constantly required.All articles have specific names and designations
CHAPTER 1. Magazine Construction and Inspection. .... 779 whichmustbe used atall times.The purpose ofthis isto insure that
2. Storage of Ammunition and Explosives... . . 783 therewill be noerrorin understanding, for sometypesof ammunition
3. StorageofChemical Ammunition . ... . . . .. 812 are so nearly alike that only by the use of proper terminology can
SECTION XI. TRANSPORTATION they be distinguished The habit of usingproper nomenclature isone
thatshould be formed from the beginning.
CHAPTER 1. Inspection of Incoming and Outgoing
Shipments . .... . ... . . .... . . .... .. .. . 827 ModelDesignations. To distinguish a particular design, a model
2. I.C.C.Regulations Pertaining toBlocking and designation is assigned at the time the model is classified as an
Staying . . .... . . ... . . .... . . .... . . ... 831 adopted type. This model designation becomes an essential part of
3. I.C.C. Regulations Pertainingto Shipper... . . 856 the standard nomenclature and is included in the marking on
4. Duties of an Ammunition Inspector at a Port the item.
of Embarkation ... . . .... . . .... . . ... . . 883 PriortoWorldWar I, thenumber of theyear in which the design
SECTION XII. RENOVATION t was adopted preceded by an"M" was used asthe modeldesignation;
CHAPTER 1. General . . . .... .. .. .... .. .. ... . . ..... . 892 for example, M1906. From theWorldWar untilJuly 1, 1925, it was
the practice to assign mark numbers. The word "Mark" abbreviated
SECTION XIII. SURVEILLANCE-GENERAL
"Mk.;" was followed by a roman numeral; for example, Shell, H.E.,
CHAPTER 1. Introduction . . .. . . .... . ... . . . ... . . ... . . 898 Mk. III.The firstmodificationofamodelwasindicated bytheaddi-
2. Surveillance . ...... . . .. . . . . . . . . . .. .. .. . 901 tion of MItothe mark number, the second byMII, etc.The present
3. Surveillance Records and Reports. ..... . . . 909
INDEX ... . .... . . .. . . .... . . .. . . .. . ... . . .... .. .. . . . ... 921 ord"erThitso pTreocvhindiecaal bMaacnkugarlounhdasfboreeinnsppuebctliiosnhedofinalladtvyapnecseofofamcmoumnpilteitoen,technicnl review in
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TM 9-1904 TM 9-1904
AMMUNITION INSPECTION GUIDE INTRODUCTION
system of model designation consists of the letter "M" followed by under which the round was assembled and the components used in
an Arabic numeral. Modifications are indicated by adding the letter the assembly. This ammunitionlot number ismarked on everycom-
"A" and appropriate arabic numerals.Thus, M2A1 indicates the first plete round of fixed and semifixed ammunition (except where the
modification of an item for whichthe original model designation was item is too small as in the case of small-arms ammunition) and on
M2. Inaddition to the "A" modificationsthere are also "B" modifica- all packing containers.It is required for all purposes of record includ-
tions. These may be either a change in the method of manufacture ing reportson condition, functioning, and accidents in which the am-
ofan item,orachange in thematerial used.Examples ofthis are the munition isinvolved.To provide for the most uniform functioning, all
M18B1 steel cartridge case and the MIBIA1 primer. Certain items of the components in any one lot are manufactured under as nearly
standardized for use by both Army andNavy aredesignated by the identical conditions as practicable. For example, in the case of fixed
letters "AN" preceding the model designation; for example, AN- ammunition, all of the rounds in any one lot consist of:
M100A1, AN-Mk. 19, AN-Mk. IV. The two designationsabove, AN- 1. Projectiles of one lot or grand lot (one type and one weight
M100A1 and AN-Mk. IV, indicate that the item isof Army design, zone).
while thedesignation AN-Mk. 19, indicates that the item isofNavy 2. Fuzesofone lot orgrand lot.
design. In recent years the Navy designations have been Arabic 3. Primers ofone lot orgrandlot.
numerals, previously they were roman numerals and some of these 4. Propellent powder of one lot.
may stillbefound.
DEFINITIONS.
Classification byStandards.
A few basic definitions are essential if one is to attain complete
Standard articles arethose which arethe most advanced and satis- understanding ofthe material which istofollow.
factory, and have been adopted by the Secretary of War. They are
Ammunition. Ammunition isdefinedas any.orall materials used
preferredfor procurement tomeet supply demands.
to charge weapons of war, including pyrotechnics in all of itsforms.
Substitute standard articles are those which do not have com- There is one point in this definition that might not be clear.
pletely satisfactory military characteristics, but are usable substitutes "WeaponsofWar"referstonot only guns,howitzers, mortars,and the
for standard articles.They are not normally in use, nor arethey avail- like, but toairplanesand soldiers as well.
able for issue to meet supply demands. They may, however, be pro-
Caliber. Caliberisaterm whigphaswidespreaduse in the fieldof
cured to supplement the supply of standard articles. an ammunition inspector. Nearly all ofthe ammunition is measured
lamited standard articles are those which do not have as satis- in calibers. A caliber is the diameter of the bore of the weapon be-
factory military characteristics as standard articles, but are usable tween opposite lands. While it is used as a unit of measure and is
substitutes for standard articles. They are either in use or available expressed in inches or millimeters, it has no unit in itself. Thus, if
for issue to meet supply demands. itissaid thatthebarrel ofaparticular weapon is30 calibers in length
Classification byIssue and Manufacture. In making use of the itdoes not mean that it is30 inchesor 30 millimeterslong, but that
Standard Nomenclature Listsand Complete Round Charts, the status itslength is30timesthe diameter ofits bore between opposite lands.
of the ammunition may be found marked as "S" or "S&M." In this Tobe ofanyuse,caliber must referto a specific weapon.
instance, the "S" indicates that the item is standard for issue only Lands. The landsin aweaponaretheraised portions of therifling
and isno longer beingmanufactured. The "S&M" indicates that the ofthe weapon, and the spaces between the lands are called grooves.
item isstandard for issue and is being manufactured. Complete Round. A complete round of ammunition is made up
AmmunitionLot Number. When ammunition is manufactured, ofall the necessary components toa chain ofevents whichwill per-
a lot number, which becomes an essential part of the marking, isas- form a desired function under the proper circumstances and at the
signedinaccordance with pertinentspecifications. This lot nurnnber is proper time. For example, a complete roundofa high-explosive shell
stamped or marked on every item of ammunition unless the item is wouldbemade up ofa projectile, an explosivefiller, a fuze,a booster,
too small. A group ofthese lots which for both engineering and sta- a propelling charge, a cartridge case, and a primer.Here, all of these
tistical reasons can be considered to be of the same standard of components are.necessary to bring about the desired function of the
quality is called a grand lot. In addition to this lot number, there is shell and thus make upa complete round.
assigned to each complete round of fixed and semifixed ammunition Small-armsand Artillery Ammunition. A most important divi
an ammunition lot number which serves to identify the conditions ding lineinammunition is that between small-arms and artillery am-
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'TM 9-1904
AMMUNITION INSPECTION GUIDE
munition.Thisdividingline isbasedon 0.60 inch.Small-armsammu-
nition is defined as ammunition fired in weapons whose bores are
0.60 inchorless in diameter, whileartillery ammunition isdefined as
ammunition fired in weapons whose bore is over 0.60 inch in dia-
meter. It iswell tonote that small-armsammunition includesammu-
nition which is 0.60 inch in diameter, and that anything over 0.60
inch must be considered as artillery ammunition.
ARTILLERY AMMUNITION.
Tactics andAmmunition. Artillery wasfirst used mainly against
fortificationsfor thepurpose ofbreaking downwallstoallowthepass-
age of foot troops in an attack. Because the hand weapons of the
defending forces were crude and of short range, the cannon of the
attacking forcecould be emplaced at close range. There was, there-
fore, no need for long-range fire, and artillery was put into position
in frontofthefoot troops.Withthedevelopmentofshoulder weapons
ofincreased rangeandaccuracy, it became necessary for artillery to
seek positions at greater distances from the opposing forces and in
therearoffriendly troopswho served toprotect theartillery division.
These conditions called for greaterrangeand power, whichin turn
necessitated improved projectiles and propellent powders. The as-
signment ofspecial missions toartillery brought about the develop-
mentofspecial ammunition with whichto accomplish these missions
Projectiles. Aprojectile isamissile, either solidorwith an explo-
sive,chemical, or inertfiller, propelled from a weapon by the force
of gases produced by a propellingcharge.
Early projectiles firedfrom cannon were iron darts, wrapped with
leather, of a size to fit the bore. These continued in use up to the
sixteenth century, when they were replaced by spherical shot. One
example ofthis shot was roughly rounded stoneballschosen because
of theircheapness.Forged iron,bronze,and leadballswere tried, but
expense prevented their general adoption.
Also, since heavymetal shot necessitated the use of a correspond-
ingly large propelling charge, too great a strain was exerted on the
feeble artillery pieces ofthe period. This frequently caused rupture
of the cannon. Stone shot laming about one-third the weight of iron,
the powder charge wasreduced in proportion, effecting an additional
economy.
Both iron andstone shot occasionally were covered with lead to
preserve the interior of the bore by reducing the friction, and to
afford a closer fit between the shot and the bore, thereby improving
the obturation, preventing the escape of gases, and increasing the
muzzle velocity and range. Hollow projectiles filled with explosives
or combustibles, and variations of canister appeared during the six-
teenth century.
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'' TM 9-1904 TM 9-1904
AMMUNITION INSPECTION GUIDE
INTRODUCTION
Shalic. Since its inception, the demand for greater and greater near the point while themain air pressure comesnear theshoulders.
range has influenced the shape of the projectile. Toward the end of When a projectile with a radius of ogive of 5 or 6 calibers is used,
the sixteenth century, cannon shot was made of cast iron and was theshapeofthepointbecomes important in determining thedirection
spherical in form. The spherical projectile was inefficient ballistically, of the air currents which flow over the shoulders.
it was erratic in flight.Because ofthe crude methods ofmanufacture, The idealshape for a projectile intended totravel through the air
a tight fit could not be obtained between the projectile and the bore with the minimum.resistance would be one ofstreamline profile and
ofthecannon. Itsroughsurfaceincreasedair resistanceand,byvirtue having a nose with an ogive curved for pushing aside the air mole-
of its shape, a maximum surface in proportion to its weight was cules with the least disturbance. It would also have a tapered or
effected by resistance. Nevertheless, the spherical form continued in conical ("boat-tailed") tail toeliminate vacuum-forming eddies in its
useuptothe advent ofrifled cannon (about 1860), when projectiles wake. The flat, sawed-offbottom ofthe type ofprojectile in use prior
were elongated to a cylindrical form with a pointed nose. to World War I isinefficient, because the partial vacuum formed be-
Factors affecting desired shape. The amount of air resistance de- hind the projectile during flight greatly retards it and causes un-
pendsupon the size,shape, and "presentation" of the projectile. Size steadiness in flight. For this reason modern projectiles are of the
is significant because of the greater number of air molecules to be "boat-tailed" type.
displaced by movement of the larger projectile. Shape of the pro- Exterior of Modern Projectiles. Modern projectiles combine
jectile has an important effect on the manner in which the mole- weight and form in the most practical way to secure a maximum of
culesare shouldered aside. "Presentation" affects both thenumberof stability and a minimum of air resistance in flight.
air molecules displaced and the manner in which they are pushed Ogive. Starting with the point of the projectile and working to-
aside. Aprojectile of2 feet in diameter displaces four timesasmany ward the rear, the first portion encountered is the curved portion of
molecules as does a projectile of I-foot diameter, since the area of the nose of the projectile. This is known as the ogive. The ogive
the cross section of a projectile varies asthe square of the diameter. describes an arc whose center lies on a plane perpendicular to the
A cone with abase diameter of 2 feet, since itsgreatest cross section axis of the projectile, with a radius usually expressed in terms of
isthesame asacylinder ofthesame diameter,displaces just asmany caliber. This radius formerly was two calibers for all projectiles, but
molecules as does the cylinder, but because of its pointed shape, it experiments have proved that a marked reduction in air resistance,
effects thedisplacement more smoothly and consequently encounters resulting in greaterrange, can be obtained by increasing theradiusof
less resistance. the ogive toas much as 10 or 11 calibers.
Weightexercises agreateffect on thepowertoovercome resistance. Bourrelet. Directly behind the ogive is a very carefully and ac-
Thus, two cylinders of equal diameter and length composed of dif- curately machined portion of the projectile, known as the bourrelet.
ferent materials, one twice as heavy as the other, would experience It isthis portion ofthe propectile which most nearly conforms to the
the same resistance to travel through the air. However, the heavier bore of the weapon. In action, it fcts as a forward bearing surface,
would possess double theability of thelighter to overcome resistance. and also helpsto centerthe projectile in the bore oftheweapon. The
Again, since length has little effect on resistance, a cylinder twice average bourrelet isabout 1/6 of a caliber in width.By having only
the length of the original one and composed of the same material, if a small bandsuch asthe bourrelet for a bearing surface, theamount
solid, would be twice as heavy and wouldpossess double the energy. of resistance due to friction in the bore is greatly reduced as com-
In order that a cone may possess the same energy as a cylinder of pared to the friction which would be produced if the whole bodyof
equal diameter, it must be longer, sinceit otherwise would be of less the projectile were to contact the lands.
wseidiegrhatti.oAnss,tthheelmeongdtehrnofparopjreocjteiclteilreepirsesleinmtistead bcoymcperrotmaiisneo,thceormbcionn-- bouBroredlye.tTahnedcyelxitnednrdiicanlgpotortitohne or£ottahteinpgrobjeacntdileisdicroecmtmloynbleyhincdaltlheed
ing energy-producing effect by means of increased weight, and re- the body. This is slightly smaller in diameter than the bourrelet
sistance-reducing effect by means of thepointed nose.
and isusually 1 to2 calibers in length.
The air resistance is affected in a marked degree by the shape of
tthhee nshoosuel.dIetrsisifsomuonrdethiamtpoirntaantshetlhlanintthhaet oufsutahlefaocrtmu,althpeoisnhta.pTehiosf tfliioRgnhotto.afItfitnhtgehebparpornjodej.cetcTitlhieleeapdbuiorduptonsoiettsorofaxtiatsth,eeirinnotofalrtidigenhtrg,btiotanwgdoiuvielsdtitoflcsytaauebsnielditroyovteair-n
is explained by the fact that as air streams outward from the point
end or tumble; its flight would be irregular and inaccurate, and the
to pass over the shoulders of the shell, it leaves a partial vacuum range would be reduced. The rotating band, by engaging the lands
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TM 9-1904
TM 4-1904
AMMUNITION INSPECTION GUIDE
INTRODUCTION
would expand when acted upon by the pressure of the gases from
the propelling charge. This expansion caused the brass tofit into the
grooves of the rifting and thus gave rotation tothe projectile.
Another early type of projectile was the "Iiotchkiss" type. This
projectile was manufactured in three parts; the forward portion of
steel, a rear portion also of steel, and the two held apart by a lead
ring. When the round was fired, the rear portion forced against the
lead ring which expanded into the grooves and thus gave rotation
tothe projectile.
Adifferent method entirely was foundin the"Whitworth° gun and
projectile.In this model,theweaponwasfitted withahexagonal bore,
twisted in the same mannerastherifling in theothertypes.Thepro-
jectile was fashioned to fit the bore, its sides being provided with
flattened surfaces of e similar pattern.
With the introduction of breech-loading cannon, the problem of
QA MDD$D giving rotation to the projectile was simplified. As previously ex-
plained, the raised portions between the grooves are known as the
lands. The boe:rrelPt of the projectile has the approximate diameter
of the lands. At the rear ofthe projectile isa smooth band of soft
metal which has the diameter of the grooves. The projectile is in-
serted into the smooth-surfaced chamber in the rear of the rifled
portionofthe bore,and then isrammed forward.The grooves engage
the soft metal of the rotating band end hold the projectile in place
whilethe tube iselevated. On the explosionofthe propellingcharge,
the projectile moves forward and the lands cut into the rotating
band, causing it to conform to the rifling. This gives the projectile
arotary motion aboutits longaxis.
Sincetheband of amodern projectilecompletely fillsthe grooves,
it prevents the escape of gas past the projectiles and centers the
projectile in the bore. The front surface ofthe band is machined to
seat itself readily in the coned seat at the origin ofrifling.This coned
seat isknown astheforcing cone. -
@HO'1mICIS8 ®Wli1TWORTH
M ro Msa The metal oftherotatingbendmust besoft enough to flow readily
to fill therifling grooves, and to prevent excessive wear of the lands.
Flgere2-- Mean:of Obtaining Notation, Early Projectiles
It must be hard enough to prevent stripping under the resistance
met in rotating the projectile and to avoid fouling the bore. Both
and grooves in the bore of the weapon, gives the projectile this ro- copper and gilding metal seem to be favored as the best metals for
tation.
rotating bands.
Before the advent of the rotating band, many devices were tried
Certain projectiles for the 155-mm gun have,two rotating bands,
in orderto obtainrotation. One means was to provide the projectile
but generally there is only one rotating band eAa each projectile for
with aseries of studswhichwere fitted into thegrooves ofthe rifling all guns and howitzers.
asthe projectile was inserted at the muzzle. This type of projectile
Fringing groove. During firing, a small amount of the copper of
was known asthe "studded" type.
the rotating band isforced back behind the 6snd and along the sur-
A second type of projectile was the"Butler" type. This projectile
face of the projectile in the rear of the band. The pressure of the
was fitted with a ring of brass at the rear of the projectile which
released gas at the muzzle of the piece and the centrifugal force of
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FOF,
TM 9-1904 TM 9-190
AMMUNITION INSPECTION GUIDE INTRODUCTION
filler of the shell through possible defects in the base. Three types
of base plates arein use.
The oldertype, commontoall calibers, consistsofaslightly dished
brass plate covering a lead disc, the brassplate being crimped to
thebase ofthe projectile.
The new type, for small and medium calibers, has a disc of sheet
brass or steel sweated to the base of the projectile with solder, or
asteeldisc welded to thebase of theprojectile.
For the larger calibers, the base plate assembly consists of a
copper cup covering a lead disc. The copper cup is held in a dove-
tailed groove in the base of the projectile by means of a strip of
lead calking wire, which is hammered down to fill the groove com-
3*fore After After pletely and to bend the flange of the copper cup. However, in large
Assembly Assembly Mockinisa caliber projectiles that are not fitted with base fuzes, the steel disc
RA PD IW$7 iswelded to thebase.
Figure 3-Assembly of Rotating Band
Painting. All projectiles are painted primarily for the prevention
of rust. The color of the paint, however, is varied for the different
rotation combine to throw out this excess metal in a radial direc- types of projectiles and thereby becomes a basic means for identifi-
tion, so that it becomes a fringe around the rear part of the band. cation. The explanation of the color scheme is as follows:
When this fringe isexcessive and irregular, itbuilds upair resistance,
lessens the stability in flight, and causes decreased range and de- 1. Projectiles filled with high explosive, such as amatol, explosive
D, TNT, etc., are painted olive drab and stenciled in yellow.
creased accuracy. This fringing is eliminated to a great extent by
cutting a fringing groove around andin the rear of the band. 2. Shrapnel and low-explosive shells are painted red. This indi-
catesthatthey contain achargeoflow explosive.
Boat-tai.l In order to reduce the vacuum forming eddies at the
base of the projectile in flight, the base is tapered to an angle of 3. Projectiles thataresolid orfilled with aninert filler arepainted
from 6 to 8 degrees. These vacuum eddies, if present, tend to hold black.
back theprojectileand thus reduce therange. 4. Ammunitiontobe used for practice ispainted blue. This paint-
Base pfdtes. Artillery projectiles containing high explosives are ing holds even though the projectile may be solid or filled with a
fitted with base plates. These are designed to prevent the hot gas black powder (low-explosive) spotting charge.
of the propelling charge from coming in contact with the explosive S. Chemical shellarepainted with a blue-graybase color, stenciled
with acolorwhichcorresponds toitschemical classification,and have
circumferential painted bandsof the $amecolor.
Projectile Fillers.
Solidshot.The earliest projectiles were spheres ofsolid metal and
depended for their effect upon their weight and velocity, no attempt
beingmade to produce effect by explosion atthetarget
Case shot. The first departure from the solid type of projectile
came with the advent of case shot. Case shot can be traced back to
the early part of the fifteenth century; it retained its original form
throughout the entire period of its use. It was i~iended for use at
closequarterswhen a volleyof small shot was required.
Case shot consisted of a cylindrical container of tin with a cast
or sheet iron bottom and top plate. The container was filled with
RA PDISM small round shotandthe voidswere packed with sawdust to prevent
undue movement of the balls due to the shock of discharge. The
Figure 4 -Base Plate Assembly
is
14
(cid:9)
TM 9-1904 TM 9-1904
AMMUNITION INSPECTION GUIDE INTRODUCTION
shock of discharge disrupted the case, and the balls were scattered surface and destroying it, permitting the projectile body toreachthe
shortly after leaving the muzzle of the cannon. Case shot was very inner layers at an instant when they are already stressed in a favor-
effective against troops at short range owing to the wide pattern abledirection.The cap also lends lateral support to the point atthe
made bythespreading shot,but when therange exceeded 500or600 'instant of impact, preventing a deformation which would result in
yards, therewas practically noeffect. disintegration of the projectile before perforation could be accom-
Grapeshot.A variation ofcase shot,known as grapeshot, consisted plished.
generally ofthreetiersofcast iron balls separated byiron plates and The cap also performsthe valuable functionofincreasing the angle
held inplace by an ironboltwhich passed through the center ofthe ofobliquity atwhichpenetration or perforation will take place, thus
plates.The effect of grapeshot wassimilar to that produced by case tending toavoidricochet
shot. Thefunctionofthe windshield istoincrease the ballistic efficiency
Explosive shel.lExplosive shelldonot appear tohave been in gen- ofthe projectile byenabling ittoovercome more readily theretard-
eral use beforethe middle of the sixteenth century.About that time, ingeffect of the atmosphere withaconsequent increase in range.The
hollow ballsofcast iron were fired from mortars: The ballswere al- windshield is ln,-Ae of brittle material and shatters on impact with
most completelyfilled with gun powder; asmall spacewag filled with thetarget.
a slow-burning composition. Theslow-burning composition was The steel shell, or body, finally does the actual penetrating of
ignited bythe flashofdischarge, and burned untilthe flame reached the armour plate, and ifloaded with an explosive filler, will explode
theburstingcharge. Asthere was noway of accurately regulating the afterpenetrating.
time ofburning, some ofthe projectiles burst during flight, but many _~Zhae-l 'r1ho shra-el nrniartile was developed during tha_ latter
of them did not explode until a considerable time after they had part of the eighteenth century as a result of the lack of an effective
struck the ground. With the development of more accurate fuzes, projectile for use againsttroopsintheopen beyond the range of case
theseprojectiles became formidable missilesagainstfortifications, and shot
were used with someeffect againstpersonnel in theopen.
The original shrapnel wasaspherical shellfilled with lead musket
Modern shell, made offorged steel, are filled with high explosive, balls mixed with the bursting charge. With the advent of rifled guns,
and upon burning a predetermined time, or upon impact, explode the form oftheshrapnel projectile has changed, but itscharacter has
with terrific energy,breaking upthe shellwalls into several hundred remained Modern shrapnel cases aremade of forged steel.The lead
fragments. Depending upon the fuze employed, they are designed balls are contained in a matrix of smoke-producing compound and
eithertoburstin theairorpromptlyonimpact,for effect against per- are separated from the.base charge by a steel diaphragm.They are
sonnel, or to penetratea short distance before explosion for the pur- provided with a time fuze designed tocause the projectile to burst
po:;uofdestruction. either during flight or on impact. Shrapnel is designed to carry the
Armor-piercing. Armor-piercing projectiles consist essentially of a ballstoapoint.ovgrtheheadsoftroopsand,bythe functioningof the
steel shell towhich is attached, usually by crimping, a steel armor- fuze and base charge, to scatter the balls with increased velocity
piercing cap, and to this cap isattached,by screw threads orcrimp- over a considerable area.
ing, a windshield for ballistic purposes. The projectile may be either Chemical shell.Chemical shellareadevelopment ofWorld War I,
filled with explosiveDor may be inertAvery important part of the resulting from the desire to transfer quantities of chemicals into
modern armor-piercing projectile is the cap. Against face-hardened enemy territory. Chemical projectiles are filled with chemical com-
armor, projectiles which would be useless without the cap are, with pounds designed to produce casualties, or with smoke-producing
its assistance, able to penetrate in bursting condition The cap is compositions for use inscreening certain areasfrom view. Very little
made of high-carbon chrome steel and heat treated so that the por-
effect isproduced by fragmentation, since the bursting charge is just
tion directly in front of thepoint of the projectile isvery hard while sufficient to crack the projectile and scatter the chemical filler. In
the skirt is very tough. The period during which thecap performs its firing chemical shell, it isimportant thatthe shell burst before enter-
functions issovery shortandthe forces which act onitare so great ingthe ground, in orderthatthe chemical be spread instead of being
that it is impossible to say exactly what takes place, but certain concentrated in and near the shell crater.
theories have been advanced and seem to be borne out by experi-
ment. It is now generallyaccepted that the principal function ofthe Fuzes.
cap is to place the armor under great stress, flaking the hardened Earlyfuzes.Afuzeisa mechanical devicetofunction the projectile
16 !-.m;1610 ~- 17
TM 9-1904 TM 9-1904
AMMUNITION INSPECTION GUIDE INTRODUCTION
atthetime or placedesired. Proper functioning of projectiles depends Adapters and Boosters. Since the small detonator contained in
upon accurate and efficient fuzes. the fuze isnot powerful enough to insure complete detonation of the
It may be saidthatfuzes, from the start, have had moreinfluence shell filler, it is necessary to have a slightly larger quantity of high
onthe effectiveness of artillery than any othersingle item.Early ex- explosive, more sensitive than the shell filler, toamplify the detonat-
plosive shell and shrapnel, moreoftenthan not, were wholly ineffec- ing wave and insure the detonation of the filler. This intermediary
tive because ofuncertainfuzes. filler is the booster. In recent years, boosters have been designed to
Early fuzes not only were inaccurate and uncertain of action, but be assembled directly to the projectile, the old "adapter-boosters"
alsowere dangergus touse.Many accidentsresulted from prematures being discarded. The fuze is customarily screwed into the booster.
caused by defective fuzes. Even with the most modern fuzes in use Boosters are used in all highexplosive and chemical shell for all guns
today, a certain percentage of duds may be expected, and the safety and howitzers.
devicesarenot infallible. The old "adapter-boosters" consisted of an adapter and a booster
The first fuzes used were short iron or copper tubes filled with which were held together as one piece. The adapter was designed
slow-burning composition and screwed into thefuze holeofthe shell. to decrease the diameter of the nose of the shell so that the fuze
The slow-burning composition was ignited by the flash of discharge could be screwed into place. The booster was simply a casing of
and, when consumed, transmitted the flameto theburstingcharge of high explosive.
theshell. Therewas,atfirst, no meansofregulatingthetime of burn- The term "bo'Aster," when applied to chemical shell, is converted
ing. Later, about the end of the seventeenth century, the fuze case . to "burster," asthefunctionofthiscomponent istobreakupthe.shell
was made of wood,sothatby boring a holethrough the outercasing and disperse the chemical filler. The burster charge is therefore
into the composition, the fuze could be made to burn approximately greaterthan in the high-explosive booster.
for a given time before exploding the shell; or the fuze couldbe cut Propellants. A propellant is an explosive which, upon burning,
to the correct length for the same purpose. propels the projectile from the tube of the gun. It is the final link
Early attempts to produce percussion fuzeswere unsuccessful, but
in the low-explosive train.
thediscovery of mercury fulminate in 1799 finally afforded themeans
of attaining this object. Some 50 years elapsed, however, before a Early propellants. The earliest propelling powder was black pow-
satisfactory fuze was made. This was the Pettman fuze, in which a der, of aboutthe same composition aswe know it today. In the six-
roughened ball covered with a detonating composition was.released teenth century,itwasused in the form ofa fine powder or dust, but
by the discharge of the piece. When the shell struck any object, the owing to the difficulty of loading this fine dust into the muzzle of
ball was thrown against the interior wallsof thefuze,thereby explod- small arms,a granular form was developed aboutthe year 1600, and
ing the composition and, consequently, the bursting charge of the contin4d in use for more than 200 years.
shell. Smokeless powder. Smokeless powder came into use about 1890,
World War 1types.Much ingenuityand labor have been expended and quickly replaced black powder as the universal propellant for
in the effort to produce safe and accurate fuzes for all purposes. artillery projectiles.
WorldWar I types were satisfactory, ingeneral, for their purpose of The firstArmy Ordnance experiments with smokeless powder were
detonating or exploding the bursting charge at the time and under with nitrocellulose-nitroglycerine, or "double-base" powder, which
the circumstances desired. However, safety devices were not suffi- type was used in small-arms ammunition until 1906.
ciently refined to insure complete safetyagainst premature action in The smokeless powder now used consists essentially of a gelati-
transportation andloading, and during travel through the bore of the nized nitrocellulose in the form of short multiperforated grains. The
piece. United States and other countries have developed powders in the
Another serious disadvantage of World War I types ofdetonating form oflong tubes orflat ribbons and cordswhich usually contain a
fuzeswas the fact that thev could not be set at will for sunerouick certain percentage of nitroglycerine.
or delay action. This necessitated a supplyof all three types in the Because of theirhotter gasesof combustion, nitroglycerine powders
field produce more erosion in the bore of the piece than nitrocellulose.
Later t.ypes Most of the disadvantages enumerated above have For this reason, the latter aregenerallyused as propellants.
been overcome in the recently developed fuzes. Theseare explained A full discussion ofsmokeless powder will be found in thechapter
in the chaptersdealingwith fuzes. covering low explosives.
18 19