Armed Services Technical Informa'tion AgenclBecause of our limited supply, you are requested to return this copy WHEN IT HAS SERVEDYOUR PURPOSE so that It may be made available to other requesters. Your cooperationwill be appreciated.

NOTICE: WHEN GOVERNMENT OR OTHER DRAWINGS, SPECIFICATIONS OR OTHER DATAXREU-=D FOR ANY PURPOSE OTHER THAN IN CONNECTION WITH A DEFINITELY RELATEDGOVERNMENT PROCUREMENT OPERATION, THE U. S. GOVERNMENT THEREBY INCURSNO RESPONSIBILITY, NOR ANY OBLIGATION WHATSOEVER; AND THE FACT THAT THEGOVERNMENT MAY HAVE FORMULATED, FURNISHED, OR IN ANY WAY SUPPLIED THE.SAI DRAWINGS, SPECIFICATIONS, OR OTHER DATA IS NOT TO BE REGARDED BYIMPLICATION OR OTHERWISE AS IN ANY MANNER LICENSING THE HOLDER OR ANY OTHERPERSON OR CORPORATION, OR CONVEYING ANY RIGHTS OR PERMISSION TO MANUFACTURE,USE OR SELL ANY PATENTED INVENTION THAT-MAY IN ANY WAY BE RELATED THERETO.

Reproduced 6yDOCUMENT SERVICE CENTER

KfOTT BUILDING, DAYTON, 2, OHIO

U NCLSFD

FOR OTFICtAL USE ONLYINFORMATION CONTMN-D IN THIS REPO

IS NOT TO BE R =.AD WITHOWT PRIOR

APPROVAL OF COMMNDING OFIC. .tIATERrotwN ARs&MALt 5ATERTOWIN s I~~m-

".., COPY ,NO. a/'

WATERTOWN ARSENALLABORATORY

* NO. WAL 71o/1o0. 0. Project Number: TB4-1OHPIA Pri.2LAW,.z.V 593-08-020

BALLISTIC EVALUATION OF VARIOUS PERSONNEL ARMOR MATERIALS

ByR. A. MuldoonPhysicist

DATE MM' 19%

WATMWNWA OW MASS

ISM

TITLIC

Ballistic Evaluation of Various PersonnelArmor Materials

Report Number: WAL 710/1044

(. i. Project Number: TB4-10H

D/A Project Number: 593-08-020

H. A. MULDOONPhysicist

W4TTI(WN ARSENAL LABURAL&I

Authorized by: OHDTB-f4aterials 9 Yarch 1954D/A Project Number: 593-08-0200s. Project Number: TB4-10HAeport Number: WAL 710/1044Priority: 10Title of 0.O. Project: Armor MaterialsFiling Title: Personnel Armor

TITLB

Ballistic Evaluation of Various Personnel Armor Materials

OBJECT

1. To develop penetration equations from available ballistic datafor Doron, Type II, bonded nylon, unbonded nylon, 24ST-4 aluminum alloy,75ST aluminum alloy and Hadfield manganese steel which express the bal-listic limit for the fragment-simulating type projectiles as a functionof the weight of target material disposed at 00 obliquity.

2. To employ these equations to determine the relative effective-ness of various personnel armor materials for protection against attackby fragment type missiles at 0* obliquity.

SUKKARY

Tests conducted at Aberdeen Proving Jrround on personnel armormaterials using fragment-simulating type projectiles have yielded thevelocity required to perforate a given weight of material per unitprotected area at 00 obliquity - for a wide variety of materials overan extensive range of target weights (10 to 70 ounces per square foot).The trends exhibited by these data are such that application of thetheory of scale model penetration is suggested. This results in thedevelopment of penetration equations of the Poncelet and de Marre formwhich accurately reproduce the terminal ballistic results over the datarange.

The penetration equations for various personnel armor materialsare listed as follows:

Data Range

Mat erial Zouat ion = oz/ft2 /in)

24ST-4 aluminum alloy VL= 435 expLE.0048 ()j 45 - 325

75ST aluminum alloy V- 417 expE. 0048 (~J 40 - 325

Bonded nylon VL =136 (f)0.49 30 - 290

Unbonded nylon VL-213 (f)0-41 30 - 295

Hadfitald. manganneseV = 17-5 (f) 0 .8 9 40 - 185steel

Doron, Typo II VL 47 (f)0.70 35 - 290

=surface density of target material(oz/ft2)

d =diameter of fragment simulator (inches)

By mAns of the equations developed the relative effectivenessof various personnel armor materials in protecting against attack byfragment type missiles at 00 obliquity is assessed.

Performance curves are presented to assist the personnel armordosigner in selection of the most effective material to defendagainst fragme-nts of known we-ight and travelling at known velocity.

CONCLUS IONS

1. Particular forms of the de Marre and Poncelet type, penetra-tion equations are found to reproduce the terminal ballistic resultsof the various personnel armor materials.

2. Of the personnel armor materials tested the following orderof decreasing ballistic efficiency is obtained at 0* obliquity:

Prim surface densities per caliber of attacking fragmentsimulator, (f), of 20 oz/ft2/in. to 170 oz/ft2/in.

a. Unbonded nylonb. Bonded nylonc. Doron, Type 11d. Hadfield manganese steelP. Aluminum alloys (24ST-4 and 75ST)

2

* -. /in. t

From 170 oz/ft 2 1i., to 0. 290 oz/ft2/in.

a. Doron, Type IIb. Unbonded and bonded nylonC. Aluminum alloys (24ST-4 and 75ST)

3. Both aluminum alloys (24ST-4 and 75ST) are everywhere equalto each other but decidedly inferior over the entire data range to theother matprials tested.

464. Zverywhere in the region = 20 oz/ft2/in. to C = 170 oz/ft 2/in.

the ballistic difference between two consecutively rated materials issmall (aluminum alloys excepted) and as f increases this difference de-creaseps until atf = 170 oz/ft2/in. all armor materials afford the sameresistance to fragment perforation.

5. Within thp region f = 170 oz/ft2 /in, to a 290 oz/ft2 /in.Doron, Type II, becomes increasingly superior to all materials whilebonded and unbondpd nylon are equal in performance,

R. A. MUIDOGNPhysicist

APPROVD:

. 1. SULLIVANirector of Laboratory

iA

!3

C UNTENTS

P ageIntroduction .. . . .. . . . .. .. . .. ... 4

Theory ... 0 .............. .. 5

A - Projectile ........ *.*.......

B -Taret Thickness.......... ..... ... .......... 6

C - Foncelet Theory of Penetration ...... ., 7

D - de Marre Theory of Penetration..................9

Source of Data....... .o....... .......... .......... 10

Calculations .................. ............. o...o...10..

Results and Discussions .*............... .. ... 11

'Jeneral Considerations .... ................ ........ 1

Table I ... ............. 0..... o...... O. .... 14

Table.11 .........o...........0....... ........ o.. 15

Table III...........O..... .... .............o.....18

I TODUC TION

Diirtn the lattpr part of World War II and especially since theoutbreak of the Korean hostilities, intensive effort has been directedtowards the development of a lightweight material of good ballisticquality. This material must be of such construction that it can beincorporated into a garment for the foot soldier and afford protec-tion against attack by fragments from high explosive and other frag-ment producing ammunition. The need for such a garment is amplydemonstrated by the fact that approximately 70% of all battlefieldcasualties are a result of wounds inflicted by fragments and otherlightweight low velocity missiles.

For the Pvaluation of the ballistic capabilities of viriousmaterials suggested as personnel armor components, Watertown Arsenalhas designed a projectile which incorporates the essential penetra-tive features of fragment type missiles. This so-called fragmentsimulator is fired against the material under investigation and thevelocity at impact recorded. From a substantial number of impactvelocity measurements over a narrow range of velocities (where per-foration is likely to occur) the protection ballistic limit (V50) iscalculated. The V50 limit represents the velocity level at whichthere exists a 50% probability that the projectile will defeat .thetarget. Then under identical tpst conditions - obliquity, weight ofbody armor per unit arpa and projectile caliber - the V50 limit dis-criminates between the ballistic protection afforded by variousmaterials.

The materials evaluated in this report include 24ST-4 and 75STaluminum alloys, bonded1 and unbonded2 nylon, Doron, Type 113, andHadfield manganese steel4 .

1. Bonded nylon panels procured from Victory Plastics Company, Hudson,Mass. Watertown Arsenal -urchase Order 52-947.

2. Unbondpd nylon purchased undpr U. S. Army Specification 7-25,entitled "Cloth, Nylon, Duck, Lightweight," dated 20 May 1947.

3. Doron, Type II, purohased from Continental Diamond Fibre Company,Newark, Delawar-. Watertown Arsenal Purchase Order 52-1310dated 20 September 1951.

4. Hadfield manganese steel purchased under Ordnance Corps TentativeSpecification AXS-1170, revision 1, dated 18 December 1945.

4

Penetration studies in the field of steel armor have yielded sev-eral general penetration equations 5 . These equations incorporate to a

varying degree the multitudinous variables presunt in a projectile -

plate interaction. For a given target material of known mechanical

and metallurgical properties, probably the most influential are theinass, diameter and velocity of the projectile and the obliquity and

thickness of the target material. Then for a projectile of knowngeometry impacting a target at P given obliquity, extensive experi-montal evidence indicates that the success of the tnrget in defeat-

nw; the projectile is larg -ely dependent upon the ratio of targetthickness,0-, to projpctile diameter, d, (the W ratio) and projectilevelocity,

4 The dependence of penetration on dimensionless parameters permitsprojectil - plate design studies to be made in scale model in thelp..boratory- These scale model tests utilize Arior plate and projec-tUles of the same quality as correspondin4 full scale components, Re-sults obtained from these scale model tests may then be used to pre-dict full scale performance.

The development of equations for personnel armor materials re-ported herein is a resalt of expressing the penetration data as afunction of caliber plate thickness and projectile velocity - thesame variables found pertinent in perforation of steel armor by kine-tic energy projectiles- The dats are found to be well represented inseparate cases by equptions of the de Marre and toncelet tyoe.

Before introdueing tie penetration forms, it will be fraitfui todiscuss the usual 3cn.le model penetration parameters to determine theirapplicability in the ev'-luation of personnel armor materiais.

A. irojectile

Five fraguient-simitlating projectiles (see figure 1) are presentlyused by the Urdnani'.e Corps in the bpllistic evaluation of personnelPrmor. All simulAtors are heat trexited to n unlform hardness of 29-31 Rockwell"c" which is the representative hardness of fragments re-covered frow detonrteQ American Shell, HE, 105 MM, MI. The geometric.and metallurgical design is such that the essential penetrative fea-tures of fragment type missiles are preserved, and also consistently

5, Armament Research Establishment, Proceedings of the Symposium oilthe Penetration of Armor, September 28-29, 1948, lrt I, "Pene-tration by Convontional Projectiles.*

5

V.,

.1- - -

reproducible exterior and terminal ballistic results are guaranteed6 ,7.These projectiles retain the @me shape and vary only in mass anddiameter. By definition, then, the projectiles are homologous, and

ml m2

dl3 dz3

where:

ml, 2 = weight of fragment simulators 1 and 2

dl,2 = diameter of fragment simulators 1 and 2

B. Target Thickness

In penetration studies of steel armor the thickness, (e), ofthe target is usually expressed in diameters, (d), of the attackingprojectile, i.e. the I ratio. It has been found that this parameterinfluences the mode and consequently the efficiency of the perfora-tion. Tests with steel armor are usually undertaken to improve thequality of steel and no sensible variation in density occurs. Thethickness employed, then, serves as an index to the most criticalcombat consideration - weight of armor required to protect a givenarea.

With personnel armor penetration efficiency also depends oncaliber thickness of the target, but because materials of widelydiffering density are studied, it is advisable to assess the rela-tive ballistic capabilities of personnel arwor materials in termsof the weight required to protect a given area,

now

m =P x 1 xw Xe (2)

6. Watertown Arsenal Laboratory Report No. WAL 760/503 - "Deter-mination of Coefficient of Drag (KD) and Development of VelocityLoss Equation. for the Fragment-Simulating Type Projectiles Usedto Evaluate kersonnel Armor Materials," R.A, Muldoon, 27 January1953.

7. Watertown Arsenal Laboratory Report No. WAL 710/1013 - *PersonnelArmor - Ballistic Evaluation of M1 and Experimental EX-51-1

Helmets," F. S. iascianica, 21 August 1953.

6

ii

where:

m = weight

P = density*

A

V = volume

1 x w = surface dimensions

4 thickness

If attention is confined to a surface area of one square foot,then

6== (3)

where:

6= surface density

From equation (3), it can be seen that the surface density,6,

is a linear function of the target thickness,e

C. Poncelet Theory of Penetration

This theory of penetration assumes that the retarding pressureacting on a projectile during penetration is proportional to thesquare of the velocity.

Then

mt = -CV 2 (4)

where:

m = mass of the projectile

= dV = V V = instantaneous deceleration ofdt dx the projectile while perforating

the target

x = distance along the target thickness

and C is proportional to the frontal area of the pro-joctile in contact with the target.

*Seo Table ILI for a list of the volumetric densities of thevarious personnel armor materials.

**Care must be taken that a consistent set of units is employed.

II

Then

C = kd2 (5)

Substituting into equation (4) yields

d _ (6)V m

Now, for homologous projectiles - is constant. Equation (6)can be written d

V d

Integrating between the limits V VL at x = 0 and V = Vo atx =e , yields

VLV o exp b (&,) (7)

where:8

VL = that velocity which will just perforate thetarget material - limit velocity

Vo = velocity level required before perforationis established

By means of equation (3) the above relation for the limit velocitymay be expressed in termis of the .ore meaningful surface density,6.Equation (7) now becomes

VL= Vo exp [ )J (8)

In the defeat of any target, all of the energy possessed by theprojectile is not utilized in achieving perforation; but, rather, someof the projectile's energy is dissipated in the form of elastic defor-mation over the area of impact and in forward displacement of the target.Vo probably represents the dissipation of projectile velocity before theperforative mechanism is Pstabliqhed.

8. The ballistic limits obtained from the equations are not as preciseas the V50 protection ballistic limit data. Because of this thesymbol V50 is abandoned in favor of VL. A reason for this devia-

tion is suggested later.

8

D. de MarrP TheorY of Penetration:

This theory of penetration asserts on the basis of diwPnsionalarguments that the energy required for perforation is a function ofthe target thickness and the diameter of the impacting projectile.

= A dme 3 - m (9)2

and

m VJJ2 =B()3-m (10)

where:

m a projectile mass

d = projectile diameter

VL = that velocity which will just perforate the

target material - limit velocity

e = target thickness

B a constant of proportionality

Now m is constant for any projectile of fixed geometric design.Therefore, -or the homologous fragment-simulating projectile, equation(1) reduces to

VL= C (f) 2

and substituting equation (3) yields

VL - k(f)n (11)

In the ideal case the constants contained in both penetrationequations described above would admit of a physical interpretation.In general, however, the penetration process is too complicated anddependent on too many variables to allow such a simple solution.Yet, the success with which particular forms of the penetrationequations reproduce the ballistic results of various personnel armormaterials does provide a basis for a better understanding of thephysical mechanisms involved in the perforation phenomenon. Moreimportant, the equations permit an accurate interpolation of theballistic performance of personnel armor and may be readily incor-porated into a more elaborate analysis of the protection affordedcombat personnel when subjected to fragmentation bursts from H.Z.ammunition.

II

SOURCE OF DATA

The data contained in this report were compiled by the ArmorBranch, Development and Proof Service, Aberdeen Proving Ground atthe request of Watertown Arsenal Laboratory. Ballistic testing wasinitiated in order to develop specification requirements for per-sonnel armor materials. The program is still in progress and, asof yet, the data obtained have not been published.

Each protection ballistic limit, V50, listed (see Table ii) forthe various target materials is based on at least 100 test roundsfired under carefully controlled laboratory conditions. The zone ofmixed results included with each ballistic limit determination repre-sents the maximum range of velocities within which a fragment impactmay either perforate or be defeated by the target. From these datathe velocity level at which there exists a 50 probability that theprojectile will perforate the target - the protection ballistic limit,V50 - is calculated. In view of the large number of tests conducted,it has been estimated that the protection ballistic limit,(V50), de-duced from these penetration tests is accurate to within _+ 10 feetper second.

CALCULATIONS

The velocity required for defeat of the target - protectionballistic limit (V50) - is plotted in all cases against surface den-sity per diameter of attacking fragment (analogous to caliber thick-ness).

If, for 24ST-4 and 75ST aluminum alloy armor, the velocity dataare plotted to a logarithmic scale while the corresponding caliberthickness of the target is expressed on a unit scale, a linear trendbecomes evident (Figures 4, 5). However, for the other materials,the data manifests linearity when both parameters are plotted onlogarithmic scales (FPures 6, 7, 8, 9). The variability of theballistic data with (l) is such that it precludes the effort de-manded by the more mathematically elegant least squares technique;accordingly, the straight line fits to the data were accomplishedvisually. This method is justified by the fact that the equationsdeveloped reproduce the ballistic results to an accuracy consistentwith the assumption that the perforation velocity is dependent solelyon the I ratio.

For aluminum alloy data plotted on a semi log scale, the slopeof the straight line is the constant in the exponential term whilethe factor by which the ex onential term is multiplied is equal tothe velocity intercept at 0.

For the data plotted on a log-log scale the slope of the straightline is equal to the exponent of the caliber thickness while the

10

I4

factor by which this term is multiplied is equivalent to the velocityrequired to perforate the target when i = 1.

In both cases the constant multiplicative factor is a measure ofthe dissipation of energy suffered in establishing the mechanism ofperforation operative over the data range, while the slope measuresthe response of the projectile to increasing target thickness. A largevalue of this parameter indicates that projectile perforation becomesprogressively more difficult with increasing target thickness. Theequations developed as a result of this analysis are compiled inTable I and plotted in Figures 10, 11, 12, 13, 14, 15 and 16.

By means of equation (3), the surface density for the personnelarmor material under investigation is shown in Figure 3 as a functionof the thickness for the 24ST-4 and 75ST aluminum alloys, Hadfield man-ganese steel, and Doron, Type II, and of the number of layers for thenylon materials. The weight of the fragment-simulating projectile typeused in the evaluation of personnel armor materials is presented inFigure 2 as a function of the projectile diameter.

Should a knowledge of the ballistic protection afforded by per-sonnel armor against fragments of a weight class different from thosenow employed be required, then the diameter of the appropriate simu-lator ma be selected from Figure 2. Now, for any ratio of surfacedensity to fragment simulator diameter falling within the scope of thedata range for a given material, the equations developed will permitan accurate determination of the ballistic performance.

RISULTS AND DISCUSSION

The equations developed are based on the assumption that the per-foration velocity varies solely with the ratio - the perforation ye-locity remaining constant when d is constant. However, extensive test-ing with steel armor indicates that with different plate thicknessesand projectile calibers corresponding to a constant, S, ratio, theballistic limit does not remain constant. This phenomenon is knownas the scale effect and is associated with the variation in physicalproperties of the armor material at different thickness levels. Ingeneral, the change in physical properties with increasing thicknesspromotes the conditions for a plugging type penetration. The net ro-sult is that at constant t ratios the larger diameter projectiles willdefeat the larger thickness plate at a lower velocity.

This same phenomenon is noticed in tests with personnel armormaterials. The magnitude of the velocity variation as a function ofprojectile caliber or armor thickness is not apparent; but it seemsthat, like steeol, an increase in target thickness and projectile cal-iber (at a constant i ratio) degrades the performance of the target.The influence of the scale effect is small, however, and is neglectedin the development of the equations. As a consequence, should subtle

I

differences in the ballistic quality of personnel aruor be desired,then recourse should be made to the data. However, in the numerouscases where overall performance against a variety of target thick-nesses is required, the equations should prove satisfactory. Itappears that the variation between the data and the equations -introduced by neglect of the scale effect - requires that a differ-ence of 100 feet per second in calculated ballistic limits be imposedbefore a priority in armor quality can be established.

Applying this criterion to the armor materials reported hereinrpveals that the following order of decreesing ballistic efficiencyis obtained at 0* obliquity over the indicated data range.

From ' 20 oz/ft 2 /in, to = 170 oz/ft 2 /in.

a. Unbonded nylonb. Bonded nylonc. Doron, Type 1Id. Hadfield manganese steele. Aluminum alloys, 24ST-4 and 75ST

From d a 170 oz/ft2 /in. to f = 290 oz/ft2 /in.

a. Doron, Type Ib. Unbonded and bonded nylonc. Aluminum alloys, 24ST-4 and 75ST

Both aluminum alloys (24ST-4 and 75ST) are everywhere equal toeach other but decidedly inferior to the other materials tested overthe entire data range.

Everywhere in the region - 20 oz/ft 2 /in. to 170 oz/ft 2 /in.the ballistic difference between two consecutively rated materials issmall (aluminum alloys in relation to the other materials excepted)and as I increases this difference decreases until at If 170 oz/ft2 /in.all armor materials afford the same resistance to fregment perforation.

Within the region " = 170 oz/ft 2 /in. to - 290 oz/ft 2 /in. Doron,Type 11, is increasingly superior to all materials, while bonded andunbonded nylon are equal.

Ov'r the range of = 170- oi/ft2/in. to - 290 oz/ftO/in. thepenetration data for Hadfield manganese steel is sparse and appearsto manifest a trend inconsistent with that observed over the lowerdata range. Because the penetration results are insufficient toestablish with definiteness this new trend, no equation has beendetermined for this range of targets.

12

These limited data for Hadfield manganese steel, although Fit var-iance with the trend obtained ag-ainst lower thicknesses, are not alto-gether too surprising. It is most likely an indication of a changein the mechanism of perforation of the armor plate. Un the basis ofth~ese fesw results, it would seem that against projectile - plate com-binations where f > 185 the performance of Hadfield manganese steelas a personnel armor component is markedly inferior. However, morefirings are needed over this data range to substantiate this conten-tion.

GENERALJ CONJ 1DSRATI(QN

The variability in shape of actual shell fra,-~sents catises a widevariation in penetrative perforwance. This renders practically im-'possible any attempt to express with quantitative precision the ter-minal ballistic performance of actual frrngments. However, cou~parativetesting at Watertown Arsenal Laboratory of bonded fabric (nylon) hel-met liners with fragniient-simulating projectiles and nctual shell frag-wents, both types of approximmtely the same weight class, has revealedthat penetration by the simulator is in good n.:reeiment with avera ;eresults obtnined uising Actual fragments9.

The penetration equations developed for simulptors permit s feirestimate of the perfornrance that can be expected from various per-sonnel Armor materials under Rttack nt 00 obliquity by nctuial frag-ments of the SAme wei4,ht clAss. 1hould future tactical requirements4eiwand that protection be provided ajainst fraginents from A differentweight class than is represented hy the simulstors now in use, thenthe diameter of an equivalent simulator can be calculatedi from~ equ..-tlon (.1) and the maximum fra.;,Ment velocity which A -riven weight ofknown material will successfully resist Is readily determined fromthe corresponding equation.

The relations developed In this report apply only when penetra-tion Is effected at (P' obliquity. However, during., projectile pene-tration of personniel armor materials at oblique attack, the wissileremains undeformed. This would indicate that perforation dnta onoblique firings could also be represented by some simple functionalrelationship which incorporates the an,,;le of Attack. This hn beenfound true in the cnise of penetration of steel Armor at obliqiiitieswhere the shot remains undeforsied.

9. Wntertown Arsenal Lnboratory Report So. WAL 710)/1013- "IEU~uNILARUI - Ballistic Evalw.tion of Mil and Experimental MX-51-1Helmets,* P. S~. Miacianica, 21 August 1953

Data Range

Material !quation C1 _ oz/ft2/in.)

24ST-4 aluminum alloy VL = 435 Flxp L.0048 ( )j 45 - 325

75 ST aluminum alloy VL = 417 exp U0048 (7 40 - 325

Bonded nylon VL = 136 (f)0.49 30 - 290

Unbonded nylon VL = 213 (1)o.41 30 - 295

Hadfield manganese VL = 17.5 (f)0.89 40 - 185steel

Doron, Type 11 VL = 47 (f)0.70 35 - 290

VL = that velocity which will just perforate thetarget material - limit velocity

- surface density of target material

d = diameter of fragment simulator

14

'1/

PZNZTRATLUN DATA AT 00 OBLIQUITr

75ST Aluminum

krotection Zone ofPragment Simulator Thickness Ballistic Limit Mixed Results

(Caliber) (InchesL V50 (F/S) (F/S)

0.22 .072 620 600.22 .156 940 1500.22 .250 1500 2100.22 .3125 2070 2700.30 .072 555 1800.30 .156 797 1000.30 .250 1022 1600.30 .3125 1280 190o.45 .072 405 150o.45 .187 643 1100.45 .3125 850 1300.50 .102 430 800.50 .187 600 900.50 .3125 770 100

24ST-4 Aluminum

0.22 .072 640 600.22 .156 1006 1100.22 .187 1150 1300.22 .250 1550 1600.22 .3125 2165 2500.30 .070 587 1200.30 .156 817 700.30 .250 1090 1000.30 .3125 1345 2000.45 .102 560 80o.45 .187 678 1800.45 .3123 900 1100.50 .102 515 800.50 .187 626 500.50 .3125 820 60

r1 4

TABLE II (CONT)

Hadfield Mangaaese Steel

Protection Zone of

Fragment Simulator Thickness Ballistic Limit Mixed Results

0.22 .030 1003 160

0.22 .037 1105 180

0.22 .0o45 1460 200

0.22 .055 1600 2700.22 .084 1840 110

0.30 .037 840 240

0.30 .055 1282 230

0.30 .080 1695 110

0.45 .030 528 1100.45 .045 668 100

0.45 .080 1133 130

0.50 .037 520 1700.50 .045 601 130

0.50 .080 986 150

DoroA, Type II

Surface Protection Zone of

Fragment Simulator Densitj Ballistic Limit Mixed Results

(Caliber) (o f )V50 (F/S) (F/S)

0.22 16.0 1055 160

0.22 32.0 1535 220

0.22 64.0 2525 220

0.30 16.5 865 200

0.30 32.6 1180 230

0.30 63.4 1920 210

o.45 17.0 673 1200.45 32.4 858 180

0.45 64.5 1365 150

0.50 25.3 698 1700.50 42.0 952 220

0.50 53.0 1115 240

16

'Z'U L,, zz COAT)

Bonded Wion

Protection Zone ofFragment Simulator Thickness Ballistic Limit Mixed Results(Caliber) tLayer.) yO (7/S) (F/S)0.22 10 1165 1200.22 20 1600 1500.22 40 2260 2000.30 10 1015 1200.30 20 1302 1300.30 40 1825 1200.45 10 830 16o0.45 20 1060 1300.45 40 1470 1000.50 10 800 1300.50 20 1015 1100.50 40 1350 120

Unbonded Nylon

0.22 11 1230 2000.22 15 1340 2400.22 22 1650 2600.22 28 1763 800.22 33 1920 1500.22 3; 2070 2000.22 2232 1300.30 11 1062 1200.30 22 142o 2000.30 45 1906 180o.45 11 950 24o0.45 22 1197 2000.45 !5 1532 1400.50 41 935 2000.50 45 1445 140

17

TABLI III

Volume Densities of Personnel Armor Materials

Volume DensityMaterial O

Aluminum alloy (24ST-4 and 230.40 ox/ft 2/in.75ST)

Hadfield manganese steel 652.03 oz/ft2/in.

Doron, Type 1I 164.66 os/ft2 /in.

Unbonded nylon 1.44 oz/ft2 /la~yer

Bonded nylon 1.60 oz/ft2/layer

18

0, 44 +0I

4 I-0 -J

2 w 3

o 0 z4C

40~~ Q J

~L LL .

I

- 0

FIUR I-

E ~.. -

[7* I

I -I... -..I~* -H"

L - I i F IK-"-~ I I F.~.F*T I

-~ FI iii-....,.~ ~ 7 K K7V~V ~..1 A-- I4. F I

-- .1.

a - I { T-4 .....--..I- - -.

VF I F I

~ I - -

I. - 1 ~ , I..-~---. I II

-j ,FI J- . I..........+-i. 7v1----------

'<In.42 F

F . , , I

* a1~ I , - F

I L~.. - TF j F . -1-- 17 2

~ 0

I 'ILF f II WATCRTOVN ARSENAL LABORATORY

VN.639-12,729 FIGURE 2

K tto

1L .0 176

Li IIU 3

E O E oN 0 PNETIN EQUr1ON FO.

I If/4 1 !

I .-r -.-IR0AT

.2 0 . ... .

o. . ... " .. . .

P, W - -- -- -- -- --- ---- --- - - - - - - - - -

-' -OI,/FT IIN, . . ...

WA TERTOWN A R8 NA L LABORATORY

-t-4200,4

r. I 9-BO.4)I

VTN,6) - O 2 73O

't ! . . . .. .

4EVC W PE RA/TG EY ":HEO ;FARIi " OF;TO, AT,'

200: - -. . 4...... ... ... .. ..

T t2o ---- _

i ,o $i . li l ;.... 150 0O ". . ........... ..... .... T ....

-. 200 --- : .

-,, -60 0 .. . . .. . . . . . . . . .

E OF MiXED SULtS0 CAL. P.30

a CAL. P.45> CAL. 0.50

40 140 0 240 2 3401-oT 2,I.

* ~~di ur.I.

WA T I R TOwN A R CNAL L ABORA T OR Y

WMA16- 6,732 flaunt s

fl -= EL -4 -- -- 9--

IMM- = -YI:Rr

M IL I_____I 1* !.j I

V. - i 01w

. ..- I2t LEG 1D:1

4-W OF . ' -

----- e-_ CAL -

- . . .. ....... ........ H

60 90 120 150 180 21024 30

M- ( 0Z./FT.2/N.)d

VWA TECRTO WN ARASE1N AL L A BORAA TOR Y

WN.639- I2.733 FIGURE 6

17

&FW

DIVVIL6PIENT, ... .,_L ... . o TONE K- - -BY T FA ENT

3 44

ATTA- ' -'sAG#

41 20001 1

CID

1-1

T . .!. . . vi - x4 .. . . ..- i. ... - ..: .2. . . . . , ] , .1

t A-4 4 2 -4- -- -

-OA ---

I , ' ,-2

.I _ __ _ ___" _ __ _ .. ... ._.. ... .. ... .. . . .. . .

60... . . .. 120 150 210 24 3- tI

_(O i./FT2/IN.

d

wA T ERA TOWN ARASENAL LABORATORY

FwN.639-12,73S FIGURE 8

t -11

_ _ _ _ _ _ _ _ ir &me_ A- I__ _ _ _ _ _ _ _ ___ _ _ _ _1 ~ ~ ~ ~ o 2 e7~91

VtsiO~ AvEA LASOR TOR

7 7iuR

1 - 1-E .

F I if

r--V..

-4LA N *Mw-

CA1. 0_

-S 7d

** -)A* -

W A T ERTO0WN ARit NA L L ABO R A TO0R

vToo.639-; 2,737 lIUR o

-KMV

WATERTOWa AREAL AO ATR

W2~~~rom o io1i 0 ,1

T.:.

-AL

A-480

- 4T

as..AAO -

57 1~ r--42Y1tiV ~ ~ CL AS ~ ~ ~

W A T ERATOW N AASEIN A L L ABO R ATOR AY

r Ieunt 12

1 -. Mo

0400 AL .2MIxD IEIIUS.

I t a s a0.33[-FAI~~N-- ~ - - -0i.FTOmt

{ILLLI "SL _

WATERTOWN AR~0sENLLSRTR

WT A69-279FIUE1

-- g 00 140 00

77111 1 I

I i I I I-

L- 1z 1 1

I i!I -I i

zii

L--

_ I I

- - ,L--~-- -

1 1-4

j VWATECRTOWN ARSINAL LABORATORY

VTN nr20,741 UISUR

- *A**__ -

-- I -

_L F

, ~ ~ A AT I||

T, IIN '

I , ; I , i I , I

Ii ___, , ,_of i

"I i + " i - -I . ..- ... .... '----l a . .

OBLIQUITY... -Ei-.

* - 4> , 4'e _ _- _ _

7TN t

(. -I) I I Il II JRI_ 1

OE 4F MIXD *ESOJLTS

80 140 6 4 s

FRUMNT 0 411

CALAD-S

CAL.*2 M

CAL 9A5&2-i- -

CAL. 05 -o

A T 9RATO VN A RSE N AL L A8ABATO0R Y

Wft.39-10742f IGURE 15

I I'D2 0 0 1 2

WATCRTO ~ ~-N ARE ILtAoRTY

vla-Z?3 IUEI

Oopies Extra CopiesPrepared 40 Watertown Arsenal Remaining 2

TECHNICAL REPORT DISTRIBUTION

Report No. WAL 710/1044 Title: "Ballistic Evaluation of VariousPersonnel Armor Materials.

TO: No. ofCopies

Commanding OfficerWatertown ArsenalWatertown 72, Mass.Laboratory File 1ORO - Attn: Mr. Goldberg 1Author 2

Chief of OrdnanceDepartment of ArmyWashington 25, D. C.

ORDIS-Small Arms 1ORDTB-Research & Materials 1ORI)TS-Small Arms Dev. 1ORDTT-Tank Automot ive 1ORDTX-AR-Zxecutive Library 1

Commanding OfficerFrankford ArsenalPhiladelphia 32, Pa. 1

Commanding OfficerPicatinny ArsenalDover , New JerseyAttn: ORT2B-TM 2

Commanding OfficerRock Island ArsenalRock Island, Illinois I

Commanding OfficerSpringfield ArmorySpringfield 1. Mass. 1

'A5

TO: No. ofCopies

Commanding OfficerWaterviet ArsenalWaterviet, Mew York 1

Commanding GeneralAberdeemn Proving GroundAberdeen, Maryland

Attn: ORDBG-Dev. & Proof Services, Armor Branch 2Attn: OIDG-Tchnical Branch 1Attn: Ordnance School 1Attn: Ballistic Reearch Lab., Mr. F. Hill 1

Comiuianding JepneralWright-Pattprpon Air Force BaseDayton, Ohio

Attn: WCRTS - Mr. D. A. Shinn 1

DirectorArmed Services Technical ILnfo AgencyDocuments Service CenterKnott BuildingDayton 2, Ohio

Attn: DSC-SD5

Chief, Bureau of OrdnanceDepartment of the NavyWashington 25, D. C.

Attn: RA31

CommanderNaval Proving GroundDehlgren, Virginia

Attn: Armor & Projectile Lab.1

DirectorNaval Research LaboratoryWashington 25, D. C.

Attn: Mr. T. W. George1

Chief, Bureau of AeronauticsDepartment of the NavyWashington 25, D. C.

Attn: Aer.-Ar-44001

TO; No. ofCopies

The Quartermaster GeneralDepartment of the ArmyWashington 25, D. C.

Attn: R&D Chemicals & Plastics BranchMr. Jean L. Lewis

Attn: R&D Division, Mr. D. Hastings

Commanding OfficerMarine CorpsCamp LtJupne, North CarolinaAttn: Lt. Com. F. J. Lewis

Naval Med. Field Research Lab.

Commanding OfficerArmy Chemical CenterEdgewood, Maryland

Attn: Dr. C. N. Herget

Commanding GeneralArmy Field ForcesFort Monroe, Virginia

Attn: Res, & Dev. Section

PresidentArmy Field Forces Board No. 3Fort Benning, Georgia

The Surgeon GeneralDepartment of ArmyWashington 25, D. C.

Attn: Med. R&D Branch

Office, Ordnance Technical RepresentativeUnited StateA ArmyDAD, Canadian Army HeadquartersOttawa, Ontario, Canada

Attn: U.S. Technical Rep. Lt.Col. J. G. Redmon

AYPROVING AUTRORITY:

Ltr. let Indorsement, letter file ORDBZ-L 461/5511,* 0.0. 4o0.112/3344-Wtn Are, dated 27 November 1953

FROM: ORDTB-Materials

i