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NWC TP 6275 




Survivability of Penetrators With 
Circumferential Shear-Control 

Grooves 


by 

J. C. Schulz 
and 

0. E. R. Heimdahl 
Research Department 


April 1981 




s 


a- 

6 . 


NAVAL WEAPONS CENTER 
CHINA LAKE, CALIFORNIA 93555 








Approved for public release; distribution unlimited. 


81 8 21 06 7 





Naval Weapons Center 

AN ACTIVITY OF THE NAVAL MATERIAL COMMAND 


FOREWORD 


The research described in this report was conducted in support of 
controlled fragmentation studies for hard target penetrator warheads 
under the Air Strike Warfare Weaponry Technology Block Program at the 
Naval Weapons Center. The work was performed during Fiscal Year 1981, 
and was funded by AIRTASK WF32395, Program Element 62332N, Work Unit 
1321051. 


This report was reviewed for technical accuracy by John Pearson. 


Approved by 
E. B. ROYCE, Head 
Research Devartment 
1 April 1981 


Under authority of 
W. B. HAFF 
Capt., U.S. Navy 


Released for publication by 
R. M. HILLYER 

Technical Director 


NWC Technical Publication 6275 


Published by.Technical Information Department 

Collation.Cover, 15 leaves 

First printing.155 unnumbered copies 


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A TITLE 'and Sutorir/e) 


SURVIVABILITY OF PENETRATORS WITH 
CIRCUMFERENTIAL SHEAR-CONTROL GROOVES 


T AuTmOP^J; 


J. C. Schulz and 0. E. R. Heimdahl 


9 PERFORMING ORGANIZATION NAME ANO AOOPESS 

Naval Weapons Center 
China Lake, CA 93555 


M. CONTROLLING Office NAME ANO AOOPESS 

Naval Weapons Center 
China L'ake, CA 93555 


5. TYPE OF REPORT 6 PERIOD COVERED 

Research Report 
Fiscal Year 1981 


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AIRTASK WF32395, 62332N 
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April 1981 


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19. KEY WOROS f Cantlnua on ravacao at da tl nacaaaary and Identity by block numbmr) 


Survivabi1ity 
Cylinders 
Penetrators 
Shear-control 


Warheads 

Small-scale firings 



29 ABSTRACT Continua on ravaraa alda It nacaaaary and Idantlly by block numbat) 


See back of form. 


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(U) Survivability of Penetraiors With Circumfer¬ 
ential Shear-Control Grooves , by J. C. Schulz and 
0. E. R. Heimdahl. China Lake, Calif., Naval Weapons 
Center, April 1981. 28 pp. (NWC TP 6275, publica¬ 

tion UNCLASSIFIED.) 

(U) Small, cylindrical, steel projectiles con¬ 
taining circumferential grooves were fired against 
simulated concrete and steel-plate targets to in¬ 
vestigate possible effects of shear-control grid 
placement on the survivability of impacting warheads. 
The projectiles fired against simulated concrete de¬ 
veloped a bulge near the front of the internal cavity. 
The presence of a groove in this region significantly 
reduced the breakup velocity, while a groove a short 
distance to the rear had no effect on survivability. 
Thus, a shear-control grid could be machined from 
slightly behind the bulge to the rear of a warhead 
case without reducing survivability while, at the 
same time, maintaining a significant amount of frag¬ 
mentation control. Against steel-piate targets, 
damage to the projectile was confined primarily to 
the front end, and a groove in the internal cavity, 
whether at the bulge location or behind it, had 
little effect on structural survivability. 



\ 




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NWC TP 6275 


CONTENTS 

Introduction . 3 

Description of Experiments . 4 

Projectiles . 4 

Targets . 4 

Experimental Procedure . 6 

Results Against Thorite Targets . 6 

Results Against Steel-Plate Targets . 12 

Conclusions.17 

Appendixes: 

A. Procedure for Making Thorite Targets . 18 

B. Photographs of Projectiles After Test . 19 


Figures: 

1. Cross-Sectional Views of Test Projectiles With 

Details of Grooves . 5 

2. Impact Behavior of Projectiles Fired Against 

Thorite Targets . 10 

3. Penetration Depth Versus Impact Velocity for 

Test Projectiles Fired Against Thorite . 11 

4. Decrease in Length Versus Impact Velocity for 

Test Projectiles Fired Against Thorite . 13 

5. Cavity Bulge Height Versus Impact Velocity for 

Test Projectiles Fired Against Thorite . 14 

6. Increase in Radius at Front End Versus Impact Velocity 

for Test Projectiles Fired Against Thorite . 15 


Tables: 

1. Results of Projectile Firings Against Thorite Targets ... 7 

2. Projectile Survival Velocities Against Thorite Targets ... 9 

3. Results of Projectile Firings Against Steel-Plate Targets . 16 


1 




















INTRODUCTION 


The shear-control method of warhead fragmentation, as described by 
Pearson, 1 ’ 2 has been employed in a variety of bombs and warheads to pro¬ 
duce fragments of pre-determined size and shape. Typically, a diamond¬ 
shaped grid is either machined or formed into the inside surface of a 
warhead case. The grid is composed of families of left- and right-hand 
spiral grooves, which act as stress raisers such that the fragmentation 
process is governed by the initiation of shear fractures at the root of 
the grid elements. The size and shape of the fragments produced is con¬ 
trolled by the design parameters of the particular grid. 

For warheads required to survive penetration or perforation of 
targets prior to detonation, these stress-raising grooves may have the 
unwanted effect of inducing premature structural failure of tne warhead 
case. It has been hypothesized that should such failure uccur, it would 
be primarily due to the presence of grooves in the highly stressed region 
near the front of the explosive cavity where a bulge often develops in 
the warhead case at the transition location between nose and wall. Thus, 
failure might be avoided by the expedient of not extending the grid 
forward into this region. The effect of shear-control grids on warhead 
survivability has not been extensively investigated. 

This report describes the results of a series of firings of small, 
cylindrical, steel projectiles containing circumferential grooves against 
simulated concrete and steel-plate targets. The grooves were located 
either at the point of maximum bulging near the front of the projectile 
cavity or a short distance to the rear of this point. In addition, some 
ungrooved projectiles were fired for comparison purposes. Similar firings 
of ungrooved projectiles only have been reported by Stronge and Schulz. 3 
The purpose of the current firings was to test the above hypothesis 


1 John Pearson. "The Shear-Control Method of Warhead Fragmentation," 
in Proceedings of the Fourth International Symposium on Ballistics, 
Monterey, California, 17-13 October 1373. Monterey, Calif., Naval Post¬ 
graduate School, 1978. Publication UNCLASSIFIED. 

2 Naval Weapons Center. Parametric Studies for Fragmentation War¬ 
heads, by John Pearson. China Lake, Calif., NWC, April 1968. (NWC TM 
4507, publication UNCLASSIFIED.) 

3 W. J. Stronge and J. C. Schulz. "Projectile Impact Damage Analy¬ 
sis," in Proceedings of the Symposium on Computational Methods in linn- 
linear Structural and Solid Mechanics, Arlington, Virginia, 6-3 Oct. 1360. 

Published as special issue of s. Computers .5 Structures, Vol. 13, No. 1-2. 
(1981), pp. 287-294. 









NWC TP 6275 


regarding the influence of grid placement on warhead survivability, the 
grooves being intended to roughly simulate the effect of the shear-control 
grid. At the same time, the results are not restricted to shear-control 
grids only, but are applicable to other stress raisers in impacting pro¬ 
jectiles. It is anticipated that additional results obtained through 
metallurgical examination of cross-sectioned projectiles will be covered 
in a later report. 


DESCRIPTION OF EXPERIMENTS 


PROJECTILES 

The projectiles were all flat-fronted, hollow cylinders, 2 inches 
long and 0.5-inch in diameter. The hemispherical front of the internal 
cavity was 0.25 inch from the front end of the projectile. The cavity 
wall was 0.04-inch thick. The grooves were located either 0.46 or 0.71 
inch from the front end, and were either 0.004- or 0.008-inch deep. 

Thus, counting the ungrooved projectiles, there were altogether five 
different configurations. Cross-sectional views of the projectiles with 
details of the grooves are shown in Figure 1. Abbreviated designators 
for the projectiles are also given (P-N, P-46S, P-46D, P-71S, and P-71D, 
where N means no groove, 46 and 71 are groove distances from the front 
end in hundredths of an inch, and S and D indicate the shallower and 
deeper grooves, respectively). All of the projectiles were machined 
from 4340 steel rods and were heat-treated to a Rockwell C hardness of 
38 to 40. 


TARGETS 

The projectiles were fired against two different targets: simulated 
concrete and steel plate. 

Simulated concrete targets were made of Thorite (® Standard Dry Wall 
Products), a fast-setting, high-strength (3950 psi compressive strength) 
concrete patching compound consisting of sand, cement, and additives to 
promote rapid curing. The largest sand grains are about 0.04 inch in 
diameter. The targets were cured for 7 days prior to the firings. The 
targets were wet-cured (with their surfaces covered with water) for 24 
hours and allowed to dry-cure (with their surfaces exposed to air) for 
the remaining 6 days. It was found that care in preparation of the tar¬ 
gets was required to ensure high strength and uniformity. The prepara¬ 
tion procedure used is described in Appendix A. 

Steel-plate targets were cut from 1/16th-inch-thick sheets of a 
hot-rolled, low-carbon steel with a Rockwell B hardness of 55. 


4 









MATERIAL: 4340 STEEL, R c 38-40 

FIGURE 1. Cross-Sectional Views of Test 
Projectiles With Details of Grooves. 

















NWC TP 6275 


EXPERIMENTAL PROCEDURE 

The projectiles were fired from a smooth-bore, 50-caliber powder 
gun. Impact velocities were measured in the gun barrel with a photo 
diode system coupled to an interval counter. The Thorite targets were 
placed about 18 inches from the end of the barrel, and the steel-plate 
targets about 6 inches from the end of the barrel. The projectiles 
impacted the targets at normal obliquity. Projectiles that perforated 
steel-plate targets were captured in a recovery trough filled with 
Celotex® slabs placed immediately behind the targets. The apparatus is 
described more fully by Goldsmith and Finnegan. 4 


RESULTS AGAINST THORITE TARGETS 


Thirty shots were fired against Thorite targets. The results are 
summarized in Table 1. Photographs of all the projectiles after test 
are contained in Figure B-l in Appendix B. Photographs of selected 
cross-sectioned projectiles are shown in Figure B-2. 

During penetration, high stresses generated near the front of the 
internal cavity result in considerable plastic deformation and the de¬ 
velopment of a bulge near the junction between hemisphere and side wall 
(Figure B-l, P-N, 2490 fps, for example). At sufficiently high impact 
velocities, a circumferential fracture occurs in the bulged region, 
resulting in separation of the front portion from the rear portion 
(Figure B-l, P-N, 2515 fps). In some cases, the front portion, although 
separate from the rear portion, was displaced backwards into the rear 
portion and the two were recovered as one piece (Figure B-l, P-46S, 

2480 fps). The fracturing of the rear portion into long, thin petals 
reported by Stronge and Schulz for a slightly different projectile 
geometry 3 did not occur. 

The presence of a circumferential groove at the front of the inter¬ 
nal cavity (in the P-46S and P-46D projectiles) did not make a notice¬ 
able difference in the appearance of the primary bulge at this location 
(although it did have a significant effect on the survival velocity of 
the projectile, as will be discussed). The presence of a groove 0.25 
inch to the rear (in the P-71S and P-71D projectiles) resulted in a sec¬ 
ondary bulge at this location. This secondary bulge is due to dynamic 
yielding along two 45-degree trajectories emanating from the tip of the 
groove which results in a wedge-shaped ring of material being displaced 


4 W. Goldsmith and S. A. Finnegan. "Penetration and Perforation 
Processes in Metal Targets At and Above Ballistic Velocities," Inti. 
"e-Sn. S;i. , Vol. 13 (1971), pp. 843-866. 






6 










• **> 



See footnote at end of table. 























TABLE 1. (Contd. 


NWC TP 6275 






















NWC TP 6275 


outwards (Figure B-l, P-71D, 2448 fps). The deformation associated with 
the secondary bulge is minor compared to the primary bulge, and does not 
appear to contribute to failure of the projectile. 

The chart in Figure 2 shows the impact behavior of the five types 
of projectiles within the velocity range studied. The solid vertical 
lines denote projectiles that bulged, while the dashed vertical lines 
denote projectiles that broke up. The greyed areas indicate a range of 
uncertainty for the survival velocity (defined as the velocity below 
which the projectiles bulge and above which they break up) for the 
different projectile types. 

Estimated survival velocities are given in Table 2. The uncertainty 
indicated in the table is primarily due to the small number of shots 
fired and not to any inherent physical randomness in the targets, pro¬ 
jectiles, or launch procedure. It is apparent from Table 2 that a groove 
at the point of maximum bulging significantly reduces the survival veloc¬ 
ity and that the amount of reduction is strongly dependent on the depth 
of the groove { 6 % for the P-46S projectile and 15" for the P-46D pro¬ 
jectile). On the other hand, a groove 0.25 inch to the rear of this 
point has almost no effect on the survival velocity for either groove 
depth (P-71S or P-71D). 


TABLE 2. Projectile Survival Velocities 
Against Thorite Targets. 


Type 

Survival velocity, 
fps 

Uncertainty, 

fps 

P-N 

2502 

±12 

P-46S 

2363 

±43 

P-46D 

2135 

±5 

P-71 S 

2467 

±7 

P-71 D 

2469 

±21 


Penetration depth is plotted versus impact velocity in Figure 3. 
Also shown are theoretical curves based on the penetration theory of 
Bernard and Creighton 5 using Thorite property values given by Stronge 
and Schulz. 3 The curve labeled ".25" radius" is the theoretical pene¬ 
tration curve for a non-deforming projectile. As expected, this curve 


3 Defense Nuclear Agency. ?ro t ;eozile PenosMsion :n :ixt<?viai 

r-zc-r;. :xnd .Jcnrutev .4r. tlusis , by R. S. Bernard and D. C. Creighton. 
Washington, D.C., DNA, November 1977. (Contract Rept. S-76-13, publica¬ 
tion UNCLASSIFIED.) 


9 










>«.* 



nst Thorite Targets 








































NWC TP 6275 


lies considerably above the experimental points. During penetration the 
radius of the projectile at the bulge increases significantly above its 
initial value, an increase not considered by Bernard and Creighton. If 
a fictitious radius of 0.291 inch (the average of the deformed cavity 
radii in Table 1) is used in the penetration theory, much better agree¬ 
ment is obtained. For a given impact velocity, the penetration depths 
of projectiles that broke up are considerably less than for those that 
did not break up. This can be attributed to a greater effective radius 
for the failed projectiles. 

The decrease in projectile length, the height of the primary bulge 
in the internal cavity (the increase in radius at this location), and 
the increase in radius of the solid front end of the projectile are 
plotted versus impact velocity in Figures 4, 5, and 6, respectively. 

Also shown are theoretical lines obtained from finite element analysis 
analogous to that of Stronge and Schulz. 3 The analysis was for an un¬ 
grooved projectile. Reasonable agreement between analysis and experiment 
was obtained. In Figures 4 and 5 the experimental points for those pro¬ 
jectiles with a groove at the cavity bulge (P-46S and P-46D) lie (with 
one exception) slightly above the theoretical lines, indicating that the 
presence of a groove at the cavity bulge results in more bulging and a 
greater decrease in length for a given impact velocity. This is consis¬ 
tent with the lower survival velocities found for these projectiles. 


RESULTS AGAINST STEEL-PLATE TARGETS 


Twenty-six shots were fired against steel-plate targets. The re¬ 
sults are summarized in Table 3. Photographs of the projectiles after 
test are contained in Figure B-3 in Appendix B. Photographs of selected 
cross-sectioned projectiles are shown in Figure B-4. 

Impact at lower velocity produced cracks on the front surface of the 
projectile (Figure B-3, P-N, 2480 fps, for example). The amount of 
cracking increased with increasing velocity, sometimes concentrating in 
a circular pattern (Figure B-3, P-N, 3230 fps). In some cases, perhaps 
due to slight non-normality of the impact, fracturing and breakup of the 
front end occured primarily on one side (Figure B-3, P-N, 2995 fps). At 
higher velocities, the steel disk punched from the target sometimes re¬ 
mained attached to the front of the projectile (Figure B-3, P-46S, 3275 
fps). 


Damage to projectiles fired against steel-plate targets was confined 
largely to the front end. Bulging occurred at the primary location at 
the front of the internal cavity, but was significantly less than for 
impact against Thorite. The presence of a groove at this location 
resulted in increased bulging and some alteration in the shape of the 









12 





DECREASE IN LENGTH, IN 


12 


.10 


.08 


.06 L 


.04 


.02 


_ Finite element 
analysis 

O P-N 
A P-46S 
V P-46D 
□ P-71S 
O P-71D 


/ w 
/ 

/ O o 

1 o 


/ 

0 / 

/ 

/ 

/ 

/ 


/ 


/ 




0 / 


/ 


0 

1800 2000 2200 2400 2600 

IMPACT VELOCITY, FPS 

FIGURE 4. Decrease in Length Versus Impact Velocity 
for Test Projectiles Fired Against Thorite. 




CAVITY BULGE HEIGHT, IN 


NWC TP 6275 


.14 _ 


.12 



_Finite element 

analysis 

O P-N 
A P-46S 
v P-46D 
□ P-71S 
O P-71D 


.08 


.06 

.04 

.02 


bo 






oy 


/ 




0 I --- 1 - 1 -*-- 

1800 2000 2200 2400 2600 2800 


IMPACT VELOCITY, FPS 

FIGURE 5. Cavity Bulge Height (Increase in Radius) Versus 
Impact Velocity for Test Projectiles Fired Against Thorite. 


14 










INCREASE IN RADIUS AT FRONT END, IN 


NWC TP 6275 







NWC TP 6275 


TABLE 3. Results of Projectile Firings Against Steel-Plate Targets. 


Projec. 

type 

Mass, 

gm 

Impact 

velocity, 

fps 

Description of projectile after test 

P-N 

20.07 

2480 

Cracks on front surface, bulge at cavity front 

P-N 

20.02 

2650 

Ditto 

P-N 

20.04 

2825 

Ditto 

P-N 

19.82 

2995 

Side of front end nearly broken off 

P-N 

20.12 

3230 

Cracks on front surface form circular plug 

P-N 

20.05 

3590 

Front end disintegrated and not recovered 

P-46S 

20.02 

2570 , 

Cracks on front surface, bulge at cavity front 

P-46S 

19.98 

2835 

Ditto 

P-46S 

19.72 

2985 

Circular pattern for cracks on front surface 

P-46S 

19.85 

3275 

Front end mashed on one side, target disk 
still attached 

P-46S 

19.98 

... 

Projectile jammed in gun barrel; only front 
portion struck target 

P-46D 

19.80 

2545 

Cracks on front surface; shape of cavity bulge 
shows effect of groove 

P-46D 

19.92 

'a 

Ditto 

P-46D 

19.61 


Side of front end mashed; circumferential 
fracture at groove 


19.92 


Ditto 

P-46D 

19.88 

. 

Front end shattered on one side, target disk 
still attached; fracture at groove 

P-71S 

19.97 

2505 

Cracks on front surface, slight bulge at 
cavity front 

P-71S 

19.97 

2650 

Ditto 

P-7 IS 

20.02 

2825 

Ditto 

P-71S 

20.01 

2980 

Cracks on front surface form circle; bulge 
at cavity front, smaller bulge at groove 

P-71S 

19.85 

3160 

Longitudinal crack in side of front end, 
target disk still attached 

P-71D 

19.88 

2495 

Cracks on front surface, bulges at cavity 
front and groove 

P-710 

19.85 

2660 

Ditto 

P-71D 

19.84 

2840 

Ditto 

P-710 

19.96 

2970 

Cracks on front surface form circle; distinc¬ 
tive shape of groove bulge apparent 

P-71 D 

20.05 

3250 

Front end shattered on one side, 
target disk still attached 


16 











NWC TP 6275 


bulge. The presence of a groove at the more rearward location produced 
a secondary bulge at this point. Those projectiles containing a deep 
groove at the cavity bulge location and fired at high velocities devel¬ 
oped partial circumferential fractures at the bulge (Figure B-3, P-46D, 
2830 fps, 2950 fps, and 3230 fps). For the other types of projectiles, 
however, increasing impact velocity resulted in increasing damage to the 
front end with no visible damage at either the primary or secondary bulge 
location. (Metallographic examination of cross-sectioned projectiles 
revealed the presence of tensile cracks at the roots of the grooves in 
projectiles fired against both Thorite and steel-plate targets. These 
appear to have been produced during unloading. The metallurgical aspects 
of projectile behavior will be discussed in a later report.) 


CONCLUSIONS 


The purpose of this study was to examine possible deleterious effects 
of shear-control grids on the survivability of impacting warheads. The 
single circumferential groove machined into the test projectiles was in¬ 
tended to represent the stress-raising capability of a shear-control grid 
in its vicinity. To the extent that this representation is valid, the 
results show that: 

1. For warheads fired against concrete targets, the presence 
of a shear-control grid in the vicinity of the region of maximum bulging 
in the warhead case significantly weakens the warhead structurally. More¬ 
over, the reduction in survival velocity increases with the depth of the 
groove. However, if the grid does not extend into the bulged region, no 
weakening occurs. Thus, a shear-control grid can be machined from slightly 
behind the bulge (half a projectile diameter in this study) to the rear 

of a warhead case without reducing survivability while, at the same time, 
maintaining a significant amount of fragmentation control. 

2. For warheads fired against steel-plate targets, the situa¬ 
tion is less clear. Damage to the projectiles fired against such targets 
occurred primarily at the front end, and a groove in the internal cavity, 
whether at the bulge or behind it, had little effect on structural sur¬ 
vivability. Circumferential cracks did occur in some of the projectiles 
containing a deep groove at the bulge; however, damage to the front end 
was already extensive. It is likely that another projectile design with 
a thinner case wall might have fractured at the bulge at a lower velocity 
with little damage to the front end. In this case, the effects of groove 
placement and depth on survivability might have been similar to those 
found for concrete penetration. 


17 





I 


NWC TP 6275 


Appendix A 

PROCEDURE FOR MAKING THORITE TARGETS 


I 




It is essential that the Thorite targets used in small-scale pro¬ 
jectile test firings be made in a consistent manner so that all targets 
have the same mechanical properties. The procedure used in making these 
targets so as to assure uniformity is described. 

1. The targets are usually prepared in batches of 10 at one 
time. This number of targets can be prepared in about 1 hour and can 
be comfortably test-fired in half a day. Target preparation is usually 
done out-of-doors in the early morning. On exceptionally hot or cold 
days, it might be desirable to work inside to avoid temperature extremes. 

2. The Thorite for each target is mixed in a circular plastic 
dishpan. The water required (1250 milliliters) is poured into the dish- 
pan first. Then the dry Thorite (4300 milliliters) is added. The in¬ 
gredients are worked with the hands (disposable vinyl gloves are worn 
for protection) until thoroughly blended and lump-free. 

3. The mixture is then poured into a clean, empty 1-gallon 
paint can. The can is filled to just below the inner lip. The mixture 
is packed slightly in the can, using the hands. After filling, the can 
is held by the bail and bounced gently on a flat surface until the sur¬ 
face of the Thorite has smoothed out. 

4. The newly filled can is placed for cooling in a tub of 
water with the water level slightly below the rim of the can. After the 
surface of the Thorite has set (about 5 minutes) water is poured into 
the can to fill it to the rim. 

5. After 2 hours, all the cans are removed from the tub and 
stored indoors. The cans are kept covered with water for 24 hours after 
preparation. At the end of this time the water is poured off and the 
surface of the Thorite is allowed to dry out. The cans are used for 
test firing 1 week after preparation. 


IS 







Hr*** 



































fl 

hf 



FIGURE B-l. (Contd.) 

Side Views of Projectiles Fired Against Thorite Targets. 








FIGURE B-2. Cross-Sectional Views of Selected 
Projectiles Fired Against Thorite Targets. 






























FIGURE B-3. Front and Side Views of Projectiles 
Fired Against Steel Plate Targets. 




























FIGURE B-3 (Contd.). Front and Side Views of 
Projectiles Fired Against Steel Plate Targets. 


















FIGURE B-4. Cross-Sectional Views of Selected 
Projectiles Fired Against Steel Plate Targets. 






























NWC TP 6275 


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1 Operational Test and Evaluation Force, Norfolk 
1 Pacific Missile Test Center, Point Mugu (Technical Library) 

1 Army Armament Materiel Readiness Command, Rock Island 
(DRSAR-LEP-L, Technical Library) 

4 Army Armament Research & Development Command, Dover 
DRDAR-LCU-SS, J. Pentel (1) 

Technical Library (3) 

1 Aberdeen Proving Ground (Development and Proof Services) 

3 Army Ballistic Research Laboratories, Aberdeen Proving Ground 
DRDAR-SEI-B (1) 

DRDAR-T, Detonation Branch (1) 

DRDAR-TSB-S (STINFO) (1) 

1 Army Material Systems Analysis Agency, Aberdeen Proving Ground 
(J. Sperrazza) 

1 Army Research Office, Durham 
1 Harry Diamond Laboratories (Technical Library) 

1 Radford Army Ammunition Plant 

1 Redstone Arsenal (Rocket Development Laboratory, Test and 
Evaluation Branch) 

1 Rock Island Arsenal 
1 White Sands Missile Range (STEWS-AD-L) 

1 Yuma Proving Grounds (STEYT-GTE, M&W Branch) 

1 Tactical Air Command, Langley Air Force Base (TPL-RQD-M) 

1 Air University Library, Maxwell Air Force Base 

3 Armament Development & Test Center, Eglin Air Force Base 

2 57th Fighter Weapons Wing, Nellis Air Force Base 

FWW/DTE (1) 

FWW/DTO (1) 

1 554th Combat Support Group, Nellis Air Force Base (OT) 

1 Tactical Fighter Weapons Center, Nellis Air Force Base (CC/CV) 

12 Defense Technical Information Center 
1 Defense Nuclear Agency (Shock Physics Directorate) 

1 Weapons Systems Evaluation Group 

1 Lewis Research Center 

2 Allegany Ballistics Laboratory, Cumberland, MD 

2 Applied Physics Laboratory, JHU, Laurel, MD (Document Library) 

1 Arthur D. Little, Inc., Cambridge, MA (W. H. Varley) 

2 Chemical Propulsion Information Agency, Applied Physics Laboratory, 
Laurel, MD 










1 IIT Research Institute, Chicago, IL (Document Librarian for 
Department M) 

1 Jet Propulsion Laboratory, CIT, Pasadena, CA (Technical Library) 

1 Los Alamos Scientific Laboratory, Los Alamos, NM (Reports Library) 

1 Princeton University, Forrestal Campus Library, Princeton, NJ 
1 Stanford Research Institute, Poulter Laboratories, Menlo Park, CA 
1 The Rand Corporation, Santa Monica, CA (Technical Library) 

1 University of California, Lawrence Livermore Laboratory, Livermore, CA 
1 University of Denver, Denver Research Institute, Denver, CO 
1 University of South Florida, Tampa, FL (Dept, of Structures, 

Materials, and Fluids, W. C. Carpenter)