memorandum report arbrl-mr-03236
TRANSCRIPT
SAD
MEMORANDUM REPORT ARBRL-MR-03236
BRL'S 50MM HIGH PRESSURE
POWDER GUN FOR TERMINAL BALLISTIC
TESTING - THE FIRST YEAR'S EXPERIENCE
Graham F. Slisby t'Raymond J. Roszak ILI
Louis Giglio-Tos .. d 41".,)
January 1983 •
US ARMY ARMAMENT RESEARCH AND* DEVELOPMENT COMMANDBALLISTIC RESEARCH LABORATORY
ABERDEEN PROVING GROUND, MARYLAND
Approved for public reoeas., distribution unl1imited.
C'z 83 01 14 014F= ..
Destroy this report when it is no longer needed.Do not return it to the originator.
Secondary distribution of this report is prohibited.
Additional copies of this report may be obtainedfrom the National Technical Information Service,U. S. Department of Commerce, Springfield, Virginia22161.
..
The findings in this report are not to be construed asan official Department of the Army position, unlessso designated by other authorized documents.
fTh un. of tvl. OaO or raeu.vera u m s i hs mportdos not oowmittute jnd.WR*o of V iruZ produt.
UNCLASSI FIEDSECURITY CLASSIFICATION OF THIS PAGE (ften Datee.aRDteeeSTUTIN
REPORT DOCUMENTATION PAGE BEFORE COMPLETING FORM
1. REPORT NUMBER 2. GOVT ACCESSION NO. 3. RECIPIENT'S CATALOG NUMBER
emorandum Report ARBRL-MR- 03236 ___
4. TITLE (and Subtitleh) S. TYPE OF REPORT & PERIOD COVEREDBRL's 50mm High Pressure Powder Gun for TerminalBallistic Testing - The First Year's Experience Final
6. PERFORMING ORO. REPORT NUMBER
7. AUTHOR(s) S. CONTRACT OR GRANT NUMEER(s)
Graham F. SilsbyRaymond J. RoszakLouis Giglio-Toss. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT. PROJECT. TASK
US Army Ballistic Research Laboratory AREA & wORK UNIT NUMBERSATTN: DRDAR-BLTAberdeen Proving Ground, MD 21005 1L162618AH80
II. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATEUS Army Armament Research and Development Command January 1983US Army Ballistic Research Laboratory Is. NUMBEROF PAGESATTN: DRDAR-BL 49Aberdeen Proving Ground, MD 2100514. MONITORING AGENCY NAME & ADDRESS(if differmt from Controlling Office) I. SECURITY CLASS. (of this report)
UNCLASSIFIEDiSa. DECL ASSI F1 CATION/ DOWNGRADING
SCHEDULE
16. DISTRIBUTION STATEMENT (of this Rpori!)
Approved for public release; distribution unlimited.
17. DISTRIBUTION STATEMENT (of the abetract ntered In Block 20, i diflefrmit from Report)
Il. SUPPLEMENTARY NOTES
19. KEY WORDS (Continue on retoe side if neceeay and ldenilly by block amber)
Terminal Ballistics Ball Propellant High Velocity ImpactInterior Ballistics M30 PropellantPenetrator Radiographic RangeTarget Pressure-Time Traces (Gun)Rolled Homogeneous Armor Hypervelocity Impact
20. ASTRACT (Ma0UMe M mver e N magwM Ideiiifr Y block nmb.)
The first year's operational experience in the BRL Hypervelocity Range isreported here. A S0mm bore by 120 caliber travel smooth bore high pressurepowder gun fires into a radiographic terminal ballistic range through an
:4 evacuated blast tank. Fifty-eight shots were fired in 1981, permitting estab-lishment of baseline interior ballistic performance data on in-bore masses from100 to 635 grams, propelling charge masses from 400 to 1000 grams, and breechpressures to 650 MPa, with 20mm ball powder and a custom 3Smm M30 propellant.Velocities u1D to 264S ml' we'. nphi.v,,-
DD FomI 3 croN riNo si ostr
"ADO N 147 Erow OF s N6 OBOLETE UNCLASSIFIED
4SECUITT CLASSIFICATION OF THIS PAGE (Wh" Date Entered)
TABLE OF CONTENTS
Page
LIST OF ILLUSTRATIONS .......... ..................... S
LIST OF TABLES ............. ..................... 7
I. INTRODUCTION ............. ....................... 9
II. THE FACILITY ............ ......................... 9
III. INITIAL OPERATIONS ........ ...................... ... 13
IV. CAPABILITIES ........... ......................... 23
V. FUTURE PLANS ......... ......................... ... 26
VI. OUTLOOK .......... ..................... 27
APPENDIX .......... ........................... ... 29
DISTRIBUTION LIST ......... ...................... ... 45
muor /o
' - st~tvtt ...--
- Dist I Spte'
3
LIST OF ILLUSTRATIONS
Figure Page
1 Physical layout of Range 309A ........ ................... 10
2 Typical push launch package ........ .................... 11
3 Current wetted ignition train and chamber geometry .. ........ .14
4 Comparison of bad and good ignition traces .... ............ .15
5 Muzzle velocity versus charge mass for 870 ball propellant .... 18
6 M30 performance compared with 870 ....... ................. 19
7 Breech pressure versus charge mass for 870 ball propellant .... 20
8 Breech pressure for M30 propellant ...... ................ .21
9 Critical yaw ........... ........................... .22
10 Operating envelope ........... ........................ 24
A-i Characterization of pressure-time traces ..... ............. .36
A-2 Illustrative example ........ ....................... .. 36
5
LIST OF TABLES
Table Page
1. Expected launch velocities from 50 mm hypervelocitylauncher ......... ... ........................... 25
2. Velocity data points needed for predictive data base ... ...... 28
A-1. Interior ballistic data .......... .................... 34
A-2. Specification and check hardness of RHA used in 1981 ... ...... 37
A-3. Terminal ballistic data ....... .................... .. 40
.7
• . .i • .:k -i. ., . . , .. _ _ - . _ •7
I. INTRODUCTION
This report presents a brief overview for the calender year 1981, of thehypervelocity Terminal Ballistics Research facility (Range 309A) of thePenetration Mechanics Branch (PMB), Terminal Ballistics Division, BallisticResearch Laboratory, Aberdeen Proving Ground, Maryland, which is an elementof the US Army Armament Research and Development Command, Dover, New Jersey.
It became apparent several years ago that the development of a number ofweapon systems would require firing for terminal ballistics data in excess ofcurrent ordnance velocities. To meet this requirement, the BRL engaged theUniversity of Dayton Research Institute (UDRI) to design and fabricate a highpressure 50mm smooth bore gun, mount, and blast tank capable of exceeding pre-sent ordnance velocities. The gun was delivered and the final report issued
L. in October 1979.1 Instrumentation and control systems were designed, fabri-cated, and installed by the PMB hypervelocity team.
Completion and operation of the facility was slowed because of limitationsin personnel. However, steady progress was made with the personnel availablewithout cutting corners or compromising standards. The facility was opera-tional in January of 1981.
II. THE FACILITY
*. . The terminal ballistic range consists of the launcher, an evacuated blasttank, a short drift space, and an impact area, with the target housed in atank. (See Figure 1.) The impact tank mounts a target holder on a rollertable. The residual penetrator is stopped inside the tank by a heavy armorsteel target butt. The full-diameter access door at the up-range end of thetank is closed for the shot, and a stripping plate stops the sabot petals,while the projectile (and pusher plate and obturator) are admitted througha 200mm diameter hole. Shielding the rest of the room from fragments is onlyan incidental function of the tank. It is primarily intended to confine dustsand aerosols and prevent their spreading. An exhaust fan discharges to theenvironment, and absolute filters keep the concentration to an acceptablelevel. Limited data on sabot discard and aeroballistics is available in thedrift space from four orthogonal pairs of 180 kV flash x-rays just down-rangefrom the blast tank's exit diaphragm, a 0.13mm thick by 210mm diameter Mylar@sheet. Three up-range and three down-range orthogonal pairs of 300 kV flashx-rays are located at the impact tank to record the striking and residualterminal ballistic data.
1Bauer, D.P., and Nagy, M.D., "Operation Manual for a 50mm Research Gun
System," University of Dayton Research Institute Technical Report, UDR-TR-79-80, September 1979 (Contract Number DAAKI1-77-C-0027).
.Mylar is a registered trademark of the E.I. Dupont de Nemours Co., Inc.
9
Lu.
oro
- ~4J0 4)
-'41'
//) 0
Go 10' 4..
.94
V4)
co9-
U.''iN~.-
ca.-
10
inOw Z w
0Ix-
w U)
< < U,0
o CI
co~ 0
I.- Io 0
< <<
z 0_ 0- I - <
z I>
LUU
OA
C!u CE)
L- 0:
U') CO
Because the facility is one of the few in existence, considerableadditional diagnostic instrumentation is included for interior and exteriorballistic work. Pressure taps are available at breech face, rear face oftube (RFT), and four stations along the barrel. Two dual channel Nicoletdigital oscilloscopes provide the capability for recording pressure tracesfrom four of these six stations and storing the record permanently onfloppy discs. Two copper crusher gages are routinely loaded into the powderchamber at the breech face to provide an independent, redundant pair of peakpressure measurements. An average of the two measurements is stored in apowder data base (resident on an HP9845 desktop computer) and is utilized toobtain pressure and velocity predictions given charge and in-bore mass.Experience has confirmed the copper crusher readings as being reliable andessentially the same as the peaks on the breech face pressure trace.
The gun itself is a nominally 50mm diameter by 6 meter travel (120calibers) smooth bore powder gun with a large capacity, high pressure, screw-on chamber. High velocities are achieved by saboting a sub-caliber penetratorto minimize the in-bore mass, and by using charge- to in-bore mass ratios fromabout 2:1 to as high as 8:1. At present, the standard launch package isillustrated in Figure 2, and comprises a simple four-petal laboratory sabot,a pusher disc only slightly under full bore and relieved at its edges toreduce weight, and a thin obturating pad.
The range supervision program currently resides on an HP9830 mini-computer* :system. This system requires that the pre-shot data be input, the correct* interlock status be verified automatically, and the instrumentation and
firing line be ready before releasing control to the operator. After theshot, the radiographs can be digitized and the velocity and yaw data reducedby computer and stored into the data base on the magnetic disc mass storage.
At present, a range supervision system is being developed which willsupervise and monitor various activities associated with each firing2 . Pro-grams resident on an HP85 desktop computer will: request, store, and printrelevant pre-impact and recovered post-impact data; query as to the rangetasks performed prior to simulation and actual firing; initialize and sub-sequently read counters; test and reduce pressure data from the Nicoletoscilloscopes; through an HP6942A multiprogramer, set delays which willsubsequently control the trigger amplifiers, check doors, valves, breakscreensfor on/off conditions, and note which x-ray units were pulsed. The radiographswill be digitized utilizing an HP9845 desktop computer (instead of the HP9830)with the Numonics Digitizer. The data retrieved by the HP85 will be sent tothe HP9845 for storage on disc. A short summary will be produced foreach round and the powder data base will be updated. The oversight functionsof the computer should further reduce the chance for data loss due to humanerror. Of course, should portions of the computer system be inoperative forany reason, the range operations can proceed with minimum interruption usingthe individual instruments and controls.
2B.E. Ringers and J.J. Spang"Aer, 'n Automated Terminal Ballistics RangeSupervision System," BRL Memorandum Report in preparation.
12
1
III. INITIAL OPERATIONS
The first order of business was to determine the powder loading curves forthe gun, using plastic proof slugs, with or without steel inserts to provide therequired in-bore mass. Two propellants were used: a generic ball or sphericalrifle powder, and a 1/3 scale experimental M30 propellant used for tank maingun studies by BRL's Propulsion Division. The spherical rifle powder used wasfirst WC870, manufactured by the Olin Mathieson Chemical Corp., salvaged from20mm cartridges, and later, H870, manufactured by the Hodgdon Powder Company.They are used here interchangeably, and were selected as being about the slowestburning commerical propellant readily available. The M30, though the residueof a custom batch, has a grain size more suited for our 50mm bore and wasexpected to provide a longer burn duration and hence, lower peak pressures fora given muzzle velocity. Once a skeleton of proof slug shots were out of theway, a variety of penetrator types were fired to check out saboting, whileat the same time, providing additional pressure and velocity data for preparingthe operating curves for the gun.
There followed a period of unsatisfactory shots. While the M30 seemed tobe the better performer, in retrospect it turns out that it was only moretolerant than the 870 of the bad ignition being experienced. The pressuretraces, which should normally display a smooth, rapid rise, and then fall awaysmoothly at a slower rate, instead often showed fluctuations. Not infrequently,the record could be interpreted as being due to pressure waves, wherehydrodynamic sloshing of the burning charge causes abnormal local variationsin pressure. In some cases, the pressure at the front of the chamber would beat a local maximum, while that at the rear would be at a local minimum. Inother cases, the record was more chaotic, with inflections, steps, bumps,peaks, and even spikes arrayed chaotically over the record.
Swollen or burst igniter tubes were the clue that the priming charge wasexcessive. Consultation with a number of people in the Laboratory'sPropulsion Division, followed by experimentation with the ignition, confirmedthis. Thin wooden sticks were used as inert simulants for the Benite igniterstrands. The 1.5 and 3.0 gram priming charges in use resulted in their beingblown violently to the forward end of the tube, blocking the forward spit holes.Comminutionof the Benite would increase its burning rate, and explain theexcessive internal pressure in the igniter tube. The blocked holes wouldresult in delayed ignition of a portion of the propelling charge, and theresulting extreme pressure gradient could move the charge, possibly breakingsome of the propellant grains, as could bursting of the igniter tube. Theincrease in the surface area of the broken propellant would be reflected inan unusually rapid rise in the chamber pressure, while the decrease inminimum size of the fragments would result in their early burnout,resulting in a subsequent rapid fall of the pressure to a more nearly normallevel.
Reduction of the priming charge to 1 gram of Dupont 700X pistol andshotshell powder seems to have eliminated the ignition problems. This caseillustrates the well-known observation that once a particularly persistent
@70OX is a registered trademark of E.I. Dupont de Nemours Co., Inc.
13
- - - . - . -- -. - . * .7 " . + o.
ouL ) in 0 N,.... COO %0u
0*I 0
%0l W 0 z0 OJn
%o(3 __ __ _ _ _ _ _ _ _ _ _ _
0 4) 0C44 ImU
$4 0NO 4J 44
cl O4.) 3:Cd .
0
LU v
00C4$ 0 9CII) 4 Cd P-4 P4
0L. I U " .4 .,1
*~~~ 0EE E a 1 o~~2EU :EbC Cd
< LLo E co < P
0d0-9-r4JC
-4 -
=
LUA
C)- 0)0
0
0.r44-I
0
00o
Lai w
x LU 4-I
(414 04Q
04 C0
L)
p.4
00k
I In
(odw) 3IflSS3SId
problem has been solved, the solution was trivial. Figure 3 details thegeometry of the wetted volume in the chamber, while Figure 4 presents a pairof pressure traces from just before and after the change to the ignition system.
The bulk of the later shots were fired for three ,,ally concurrentpurposes: to develop and prove appropriate launch packages; to generateterminal ballistic data (which in turn served to help nheck out dataacquisition, reduction, and storage procedures): and to continue to expand
* the pressure and velocity predictive data bases for the gun. These databases are exploited by a portion of the range supervisor computer program,which generates a best-fit prediction of velocity and pressure before theshot. Both are treated as functions of only powder loading and package mass.
*. In an unacceptable shot, the shape of the pressure-time curve cannot be re-presented by a few parameters (for example, peak pressure and time), and onewould not expect the peak pressure or velocity to be representative of anormal shot. Thus, the peak pressure data from shots displaying erratictraces is dropped from the predictive data base to ensure accurate prognostica-tion. The unrepresentative pressure data is nonetheless retained in theexperimental results data base and factors into the safety margin that mustbe allowed to reduce the probability of overstressing the system. The velocity
*data seems to be much less sensitive to a poor burn, and is only unrepresenta-tive when there is evidence of gross package failure. This is interpreted asbeing due to the rapidity of burnout relative to the in-bore residence timeof the package, the smoothing effect on pressure of the flow down a long tube,and some nebulous relationship connecting these and other factors with themuzzle velocity by way of an integral involving the base pressure-time curve.
A total of 58 shots were fired in 1981, and out of these, there was noSa priori reason to reject 50 of them from the velocity predictive data base -
36 with the 870 powder, and 14 for the M30. The 870 data is plotted in Figure5, and the M30 data is compared with the baseline performance estimate of the870 in Figure 6. Twelve additional shots with 870 powder were performed bythe contractor who supplied the gun, before delivery.1 Their velocity datawas significantly different from ours. though the difference is not worrisomebecause it is small, and probably due to differences in instrumentation and
.* setup. The breech pressure data was more erratic than the velocity data.Thirty-eight shots could be used for the pressure predictive data base - 27for the 870 and 11 for the M30. These are plotted in Figures 7 and 8.Comparing the two performances indicates that the M30 subscale propellantprovides significantly reduced breech pressures for the same package andcharge mass combinations, while comparing the velocities from the two pro-pellants indicates a similar but slight (maybe 100 m/s) advantage to theM30. Thus, it will be used to obtain maximum velocities where extremes ofpackage and charge mass are experienced, by permitting reduced sabot weights.
4' The terminal ballistic experiments to date have involved two classes of
penetrator, a long and a short hemispherically nosed right circular cylinderof soft steel. Except for two multi-plate targets, the targets used were
* simple armor plate struck at normal incidence. Penetrator masses ranged
. from 62 grams to 212 grams, and velocities to 2.6 km/s with the lighterpackages. Masses and velocities, and target thicknesses were dictatedeither by the need for specific performance baseline data, or by the threatbeing simulated. Where the penetration was expected to come within about50mm of the back face of the target plate in a semi-infinite target a second
164
plate was added to supply inertial confinement. Material availabilitysometimes dictated that several plates be used to achieve the thicknessdesired. In these cases, the mating faces were selected to give good con-tact, and the plates cleaned of weld spatter or whatnot, though the millscale was left on. The thinner plate was struck first, but even under thesecircumstances, plates would separate before perforation, as evidenced by thepetalled exit hole in the first plate. The second plate frequently showed nomaterial evacuation, raising the possibility that the termination of penetrationtended to be "attracted" by the free boundary. Witness plates were includedbehind one monolithic target to provide experience with behind-armor debrisdata collection. In one sense, the product of the year's shooting is a terminalballistic data base comprising data sheets and radiographs, from which con-siderably more data can be extracted than is reported here. The results areavailable to any interested researcher. It is our intention to publish detailedterminal ballistic data reports from time to time as enough logically relateddata is accumulated.
High yaw plagued most of the shots until the package design was improved
in October (shown earlier in Figure 2). Since then, the long rod shots have
shown low yaw, while the yaw on the short rod shots have decreased, but not
been eliminated. Projecting the yaw back to where it is zero, the problem
seems to arise at the ejection of the shot from the muzzle, rather than at the
blast tank diaphragm.
Just how much yaw is acceptable has been the subject of a growing amount
of debate in the terminal ballistic community as penetrators have grown longer,
and velocities higher. To shed some light on the subject, consider the situa-
tion shown in Figure 9. If a penetrator of diameter D and length L, yawed at
an angle e, creates an initial hole which has a minimum distance, M, from the
penetrator periphery at strike, then the penetrator may proceed into the
target undisturbed as long as its periphery clears the initial penetration.
The limiting case, where the tail justs touches the hole, is shown in Figure
9a.
It being difficult in general to determine M, one can simplify the problem
by assuming that the penetrator nose generates a circular hole of diameter H
at some undetermined plane in space, and the limiting yaw occurs when the tail
just touches this circle (Figure 9b.). This may be expressed as:
= arctan (D -) ()~2L
An interesting phenomenon associated with yawed impacts that can be seen in
thick targets is that the penetration channel actually inclines in a direction
opposite to the striking yaw by an angle, a, determined by the (presumably
uniform) relative erosion rates of rod and target as reflected by the ratio of
penetration depth to projectile length, P/L (see Figure 9c.). Our steady-state
hole diameters are not known before the shot, so that our limiting yaw figures
are empirically determined. How much beyond this limit the yaw can be without
affecting penetration is undetermined, but the numbers should give a good feel
for data quality. The terminal ballistic data is tabulated in the Appendix,
in Table A-3. There beingrelatively few interrelated shots, the data were not
4plotted. This will be done in next year's report.
17
3.0 100
SyblPk.Ms
2.5
(a
*3t asnoeo 100
E2.5
3500-~ A 300
3500
LI
N1.0-
Maximum0.5- SHOTS 1-58' Charge
Volume
0 IIIII0 200 400 600 800 1000
CHARGE MASS (g)
* Figure S. Muzzzle velocity versus charge mass for 870 ball propellant.
M30 SUBSCALE(Package Masses in grams)
_.M30 ---- 870
3.0
Co 200
2.5 -300 1 & 265
. \, 40020000
20 500> 2.o 056Uj
000-Jw
-,:" .. 600
1.5 SHOTS 1-58
600 800 1000
CHARGE MASS (g)
Figure 6. M30 performance (data points) compared with 870 (light broken lines).The M30 propellant can achieve velocities up to about 0.1 km/s over that of the870 propellant for light packages. There is not enough M30 data to draw anydefinitive conclusions.
'" 19
.4
700
600 400
615- Maximum Design Pressure600
WC-8 H -870 200
500- Legend: 0
- 100+ 200
400 -a. 289-358
w 400 0
,300- 600* U,
IX (Open Symbols
I are UDRI Data) 100w 200-
0 SHOTS 1-58
and UDRI DATA
2pts
00 200 400 600 800 1000
CHARGE MASS (g)
Figure 7. Breech pressure versus charge mass for 870 ball propellant.
2')
M30
600
+ 563 g PKG..
5001000 g PROPELLING
,1~ CHARGE~400 +
LU300
W 400 g PACKAGEw 200 MASS
100 SHOTS 1-58
00 200 400 600 800 1000 (9)
PACKAGE MASS (UPPER CURVE)CHARGE MASS (LOWER CURVE)
Figure 8. Breech pressure for M30 propellant. Due to the small numberof shots, the data is plotted versus charge mass for a 400 gram in-bore mass, and a single 563 gram point, and versus package mass for a1000 gram propelling charge mass.
21
YAW , ~,
9a GENERAL CASE: e=ARCTAN()
H
(H-D~9b UNIFORM HOLE DIAMETER APPROXIMATION: e,
L P INTERFACE-PATH
6 - SRKING
VELOCITY
9c INCLINED PENETRATION CHANNEL DUE TO YAW:
ARCTAN =ARCTAN 8P P/L P/L
Figure 9. Critical yaw.
IV. CAPABILITIES
The operating envelope for the gun is generated from the velocity database for 870 powder in Figure 10. (It is not done for the M30 because only
a small amount remains, and we do not intend to use it routinely.) The curvesindicate that little gain in velocity could be achieved with a package mass
less than 100 grams without reducing chamber volume, so the upper limit onvelocity is about 3 km/s (9500 ft/s) with the chamber holding its full one
kilogram charge. As package masses increase, velocity continues to be limitedby chamber volume until, when the package mass exceeds 500 grams, the chamber
pressure reaches its design limit of 615 MPa. Beyond that, the charge massmust be dropped accordingly to stay within bounds.
One translates in-bore mass to projectile mass by invoking a few assump-tions about package design, given the projectile geometry dictated by the
threat to be simulated and by other practical constraints. The minimum package
mass would be limited by overall length and design (25mm isprobably a practical
lower limit on length). A self-obturating carrier without pusher plate wouldminimize mass for low pressure launches and light weight projectiles. One could
achieve realistic velocities at masses up to several hundred grams for short
projectiles such as simulants of explosively projected fragments. As the lengthto diameter ratio grows, a pusher plate becomes necessary to spread the load on
the plastic obturator. 25 to 40 grams are realistic pusher disc masses depending
on pressure. Conventional packages of the design shown in Figure 2 have been
used to launch 125 gram, L/D 3 steel rods at 2.5 km/s with a 260 gram package
mass and the maximum propelling charge.
One of the most pressing areas of concern is to obtain terminal ballistic
data on typical anti-tank long rod penetrators at velocities in excess of
current ordnance velocities (i.e., greater than 1.5 km/s). Future weaponized
penetrators could be expected to span the range of 2 to 6 kg, depending on
launch means, have a density of about 18 g/cm , and a length to diameter ratio
of about 20. One would need to work at some reduced scale to simulate this.
(Indeed, isotropic scaling is used frequently to permit obtaining terminal
ballistic data on threats from anti-tank rounds to explosively projected
fragments -- in any situation where launching a full-scale item exceeds the
capacity of the laboratory system, or where reduced cost, short lead time, or
better instrumentation dictate.) Armor team experience has shown that there
is very good correlation between quarter-scale and full-scale long rod
penetrator work when velocity and hardness are identical between full-scale
and replica. Less severe scale factors (greater than h) should produce even
more believable correlation. The isotropically scaled simulant of a full-
scale projectile is usually a simple hemispherically nosed right circular
cylinder, whose length is that of the original multiplied by the scale factor,
and whose diameter is picked to result in a mass that of the original article
divided by the scale factor cubed.
Realistic scale factors that could be-used are, 1/2, 1/3, and 1/4. The
associated package mass is determined primarily by the rod mass, the length
of the simulant, (as the bore must be filled with plastic for about 3/4 of
the length of the rod) and to some extent by the chamber pressure, which
dictates the thickness of the pusher plate. Package weights figured for the
range of threat round masses and the three scale factors mentioned are listed
4 in Table 1., as are the expected launch velocities. Changing to a more
23
.4 . . i < . . .• . • _: ..... . .. .. .. . . .. . .: ... .. ... . .: . . .
t-[-~g
3.0OPERATING ENVELOPE
62g(H 870 PROPELLANT) 50g - 2 125g
1981 Explosively .'. .2.5 faunched .II
fragments 300gPKG. MASS- i i ;
100
E 2.0 TANK MAIN GUNPENETRATORS: ' b
ISAE- LPRESSUREi O~u>1.5 /SA / 20LIT
FULL SCALE LIMIT
(Diagnostic)MA IU1.0
VOLUME>,
0 250 500 750 1000
CHARGE MASS (g)
Figure 10. Operating envelope. The gun can profitably fire simulantsof tank main gun penetrators at 1/3 and 1/4 scale, as well as short seg-ments of full-scale long rods for target diagnostic purposes. Theshaded region at the upper end of the velocity range indicates the areafor which the gun is uniquely well qualified. The circles indicate thepenetrator weights actually fired at 2.5 km/sec.
24
.2 - - - -
sophisticated sabot design such as those seen on real rounds, can be expectedto increase these velocities somewhat, but not dramatically.
Table 1. Expected launchvelocities from 50mm hypervelocity launcher
L/D 20 high density penetrator of three masses atthree reduced scales.
VELOCITY (km/s)
Full Scale Mass 1/2 Scale 1/3 Scale 1/4 Scale
2kg 1.8 2.3 2.5
4kg 2.1 2.3
6kg --- 1.8 2.2
All traditional terminal ballistic procedures are possible at the facility,e.g., limit measures of armor or penetrator performance by V5 0 or eSO techniques,
lethality or vulnerability studies using witness plate or recovery packs,but the most heavily used technique is certain to be the Vs - Vr limit velocity
procedure. In this technique, the target configuration is attacked at anumber of vc~ocities from below the limit to well above the limit velocity,and the residual .elocity is plotted versus the striking velocity. Anappropriate form is fit to the data, and the point where the function lasthas zero residual velocity is called the limit velocity.
For this procedure, as well as behind-armor debris studies, the 300 kVflash radiographic instrumentation is invaluable. Each channel provides anarchival record of all six degrees of freedom describing the position andorientation of each rigid particle in the film image for which a distinquishablefeature is visible -- three coordinates of position and three of rotation --with a redundant measurement of the position along the downrange axis of thetwo features used to compute these six values. In reality, it is not possibleto determine the roll without making special preparations of the object beforehand. When the position information is coupled with the timing information,this provides a complete kinematic description of the event at each of threetimes immediately proceeding and three following the impact.
There has not been a long enough period of routine operations to havehad an adequate basis for costing, and the rather unusual constitutional,legislative, and administrative strictures on military fiscal matters makeit difficult to accurately determine the cost of doing business, so thecosts cited should only be treated as very rough estimates. However, theyare in line with experience in full-scale and quarter scale range operations.
25
At present, the full time efforts of an engineer and three technicians areproperly charged to the facility. This staffing level is not generous enoughto permit the installation and shakedown of the equipment to run concurrentlywith ballistic testing at a rate which would try the capacity of the system.However, when in routine operation, under the most favorable conditions, andat this staffing level, we should be able to fire about 150 shots per year.Current annual labor and direct overhead rates are approximately $60,000per person for estimating purposes. The BRL shops can prepare the targetand launch package for simple shots in about 10 labor-hours at the same rate,when working in lots of 10 items or more. Test material costs are about$100 more per shot, as are the costs for other supplies and services pro-ratedon a per-shot basis. Thus, the cost per shot runs less than $2,000 for laborand materials.
V. FUTURE PLANS
The first order of business is to finish out the range as the instrumenta-- tion is received, and to make improvements as initial operations indicate.
This involves finishing the control and signal wiring and changing therange supervision program over to the HP 85 minicomputer, installing an opticalalignment system in the gun and impact areas, designing a self-aligninghydraulic jacking system to seat the package, and several facility improvements.A packaged exhaust system with a suitably high stack is being procured and willbe installed when received, eliminating reingestion of vented propellant gasses.
A spare launch tube must be procured. While the wear in the rear of thepresent one is not excessive, it is beginning to show numerous small longitudinalcracks, auguring the onset of heat-checking and increased wear rate. At present,after about 75 total shots in the gun, many at less than full charge, the first200mm of the tube is worn uniformly 0.15mm. No wear-reducing means were employed.Experience with the branch's 26mm smooth bore guns has indicated that as obturationhas progessively improved, and as silicone grease has been used in addition toTiO 2-wax as a wear-reducing measure, tube life has risen from about 60 to about
100 shots. The throat geometries and operating pressure ranges on these gunsare significantly different, so the lifetimes should not be directly comparable.At the same time, though, we just don't know if there is a whole lot of usefullife left in the current tube. We would like to change the design of the re-placement tube to that suggested by the University of Dayton Research Institute.The bulk of the wear occurs in the first few hundred millimeters of the tube, sothis is made as a sacrificial section, and is replaced as needed, leavingthe rest of the tube to be changed only every 500 shots or so. As time permits,design studies are to be done with the goal of possibly replacing the screw-on powder chamber, breech plug, and ignition system with a suitable set ofreadily available military components where practical, to speed up loadingand increase safety. This includes a drop block breech, better powderhandling means such as a case, and stock electrical igniters.
Projected operations for the immediate future are to proceed with anumber of terminal ballistic programs, and at the same time to finish offthe firings to provide a minimum set of data relating pressure and velocityto package mass over the operating regime of the gun. This is to be doneby adjusting the sabot, obturator, and pusher geometries used on a terminalballistic shot to match a needed in-bore weight. Table 2 lists the data
26
needed at present to complete the data base. The most pressing operationalproblem is excessive yaw on short packages. We will first change the sabotdiscard scheme somewhat. If this isn't successful, the next area to beaddressed is the muzzle blast region. Currently, the gun has a muzzle exten-sion several bore diameters long and about three times bore diameter. Thiscreates a constriction on the free expansion of the muzzle blast on shotejection that may contribute to the yaw. If necessary, this extension willbe replaced with a launch tube extension opening out abruptly into the evacuatedblast tank, mitigating the effect of the muzzle blast on the package to someextent.
Efforts to reduce package weight will continue, in parallel with the designof simulants for real and postulated anti-armor long rod penetrators, whichwill be launched to demonstrate the system's capabilities. Some form of pusherplate deflector and sabot stripping system will be added, but the opticalalignment system is needed to align the deflector to the shot line. Sabotstripping and other conditioning arrangements currently in use in the quarter-scale ranges will also be added.
VI. OUTLOOK
The first year's operation of the 50mm smooth-bore hypervelocity launcherhas shown moderate progress, perhaps less than our original optimistic expecta-tions. The experience gained, however, is very valuable, and will be used toimprove operations in the current year. A number of problems have been over-come, and the launcher has been demonstrated to be useful for generating abroad range of terminal ballistic data on long rods at conventional and increasedvelocities, as well as simulated explosively projected fragments. Installationof long-awaited equipment and its shakedown will continue for the first halfof the upcoming year, in parallel with terminal ballistic studies, and then itis expected that the facility will be operating essentially full time onresearch.
4
27
Table 2. Velocity data points needed forpredictive data base
Package Propelling Charge Number ofMass Masses Points(grams) (grams)
H870 Propellant
100 800, 1000 2
350 400, 600, 900, 1000 4
400 900, 1000 2
500 450, 900, 1000 3
635 450, 800, 1000 3
14 points
M30 Propellant
200 400, 600, 800 3
400 200, 400 2
565 600, 1000 2
800 400, 500, 600, 700, 800 5
12 points
'4
II
APPENDIX
Interior and Terminal Ballistic Data
29
The detailed interior ballistic data for the year is presented in Table A-i.
The "priming" column describes the amount of propellant in the 300 H&H magnum
priming case. Its nominal capacity is 3 grams of 870 propellant. The igniteris described in terms of tube geometry and igniter composition and type. Theoriginal steel igniter tube was used repeatedly at first, but discarded when
it first cracked between two spit holes on shot 8, then swelled ominously onshot 9. Igniter tubes were then cut from M83 military igniters and modified
to fit in the breech plug. These essentially lasted only one shot each.Following this, heavy walled brass tubes mimicing the military design wereused. The number listed in the column (e.g., 81006-1) is a sketch numberdescribing the geometry. Except for a cut-off one on shot 54 that simulatedthe original short tube, all were essentially full chamber length. Again,until shot 50, they were damaged enough so that they were usually discardedafter one shot as a precaution. The igniter tube in the figure showing the
current chamber geometry (Figure 3) is 81006-2. The final priming composi-tion settled on was strands of Benite, a military igniter composition.
Typically, 14 full length strands are put into the tube, occupying roughlyof the cross-sectional area, and weighing about 20 grams in the referenced
tube. The "package fit" column is to be used in the future years to record the
force required to seat a projectile in the gun tube. The "maximum chamber
pressure" columns describe the average of the pressures measured on two coppercrusher gages at the rear of the propelling charge ("Av 2CC Gage @ Sta 1"),
and the peak value of the two piezoelectric gage traces, (no matter how bad
the trace), one at the rear of the chamber (station 1) and one at the front
end of the chamber (station 2).
The column headed "shape" requires some additional clarification. To
determine the cause of the unacceptable ignition traces, they were first
characterized by the degree of deviation from a smooth curve, and then by the
number of these features overlaid on a smooth trace. Figure A-1 gives the
name assigned to the series of increasingly bad features, and the abbreviation
used in the column. The abbreviations selected are a bit unusual so as to
avoid duplicating standard abbreviations used by the authors on other types
of data. The peak or maximum in the smooth data is not counted in counting
the number of pathological features, as illustrated in Figure A-2. In some
instances, the features are on the falling side of the traces. These features
are reported as a series of abbreviations. In Figure A-2, the illustrative
curve would be called inflection, peak, peak (three features) and be listed
as IPP. For only a single feature, one symbol is used, and for two, two.
An asterisk in the column labeled "PPDB" indicates that the peak pressure
has not been included in the (peak pressure predictive data base, and
similarly for the column labeled "VPDB" (velocity predictive data base). A Cl,
C2, etc. in the comments indicates a comment that was too lengthy for the
column and is listed at the bottom of the particular table.
i,3- 31
C.
-4
0P4
VPDB
MUZZLE r- O~'0-\C0 m 00m '40c0 0 m C1(4 0t-('
VELOCITY"- fl M 0Id0nMr tn o 4" 4\ 0 ) DC D%
~TUBE
~CASE
* PPDB
p4 4J41~ C-4 SHAP icd aI IL0)n r- ic
Er c RES I I I nf-0f 0 4r 0 \ CD\ 4%1 " \ 0
04J t*J "
,SAP U 0 uea W u u'~.4- u 1--40 U
.4 lyj r- 0
cd > r00 -4 00 n ~t0 00 V MO -It ~.0u MPRESS~0 000000O 0001
4 00000 00000 0000
4in t
04 Lu P- OEAT OHAY NEFREC I N L HT
4) 00 0000000000000 000000m00 000000 0lLnni
a TYP OIGINAL STEELTUBE000 TELTUE M8)
u 002.C , )0 a LI W7 0~ Q
ooj .00 00 co0 00 00 o0 0 00 0 c o0 00 0
404
4 (
If) If %OU)n
VPDB
O) M 0 %o V4 Lfn -c40L) c tnv 0 4'1 0 04J MUZZLE v0 N Qt* NI ~ O -oa tcqa 4o ic r-.( C4 1 0 I -F
w imao,0o m I-e 0 -fu VL I Nl 00 r Z I 4 eo VELOCIT , '4 4 .. "- 1. 4 P4 -- 4 -4 C4 N N
~TUBE go C.-
0CASE41'o00 PPDB .
tn 0
~CAE NO GAGES IN STATION TWVO -
o 0 4-'
9!~~O 0 e m%
.0 Q< - P-4~ CL. to 1evSHAPE LinI )c 0
04 1- IcU. 0 3:
+a PRESS ~ Ln i 0n -eef~ 'CO (D0 0- oL ,M r iI I-t1,0 00d V) m MgOU eqmm-eM- $ - it% L .0
cor4 0 4-Ju Ccj 'G v Go r- .-i 0m% t% D0 - - 0 n% %b 4 A
bn m m ol m " f~f) lem 4 n v-. S~~%0UO Ln t-qd l) 4-'
0 ua%. 4 .% -- N0 Dar r 0m \ y \0 44 4J a)
0 < c0 ; 0;0' 0 1'OIJ4Lf'0 4O~U -;4
0 3vmt)L ) 0c -c f al a~~4) CAtftf .0-'4 04L C4
r- 00 0 0 0 )0 0 0 0U Uz D Nr 0-~r 0a r Lr" 0 N w 0 CD0 000 C
1-4 r. f- I 0 0 00000P,00 t 0c 4m1- na 0 00 *,4 0)P4~coo~ r- 10I- -O O rN
W0 a. a0, r,0 0 0 Q( 0 0 0 (
S20-21 GRAMS n-0
co ~- BENITE STRANDS k_____ 00.0
u TYP -81006-1- 81006-2 + tN
0 boc0 0
.4ClO 0C4 OOOC-'0 d 0
4SHOT CeIt eq N ,4r4 m r J~~f~dto) m tln mfI~ m m UUUmleU
33
VPDB
MUZZL - 4 Lf Ln (4 b e-4 0U Ln 0 Oaqr0 LUnLI4J MUZZLEt'n 'O 00 0 -4 000 m) -e 1000 tn t t9: 4 m WL) L I Ln U o M, t~n " W) Z Lfnet0 VELOCITY i qr qe qe r 4. q r 4a
ob a~
u w 4J .5o *- U0 PPDB., , 4
is 4
*c, SHAPE w 6 .clL
I-4L 0 V M . m 00 0) 0 Z i- a)
P ZnPRESS~ r coro 00le00 t-nL m O04% on
U -SHAPE c,) i~ 0. 4UU'44 0< z0 P000 td.IJ O
wU 0) '0 %o-~~ Ln -e r -4UL r I IJ4JPRESS 9. C a 000o00 r-.Lf) O0 -4 q-e 0 t-I IPR4
-4 4o C w' WU) co r~0- 00o en .j'-0 00 0 It0 00~ m % O!m.4O'
U1 U W L 0 - "o00 00 e . m r-, 4e qi (%J4 .4 4 t-.F4W
CU 0 OL0 TIGHT EXCEPT 56 W cn.0 cn ( o 1 -40 co -4 4
m nr- t '0U~' *U*C'4 co t tn o 0U 00 00
'f%0 't %0 Un a.'. 00 0000000 00Q0 +.) %00m 1 I 4 C C4~ C14e. (NJ e' n~ e 04 LI)n I~ " eq 00
4J ba .- f 9to 0 0 000 ,4 00. -4
aZ CD 000 00 00 Q nC>c 0L0 U0 0zt n00 /L L Ln 0 00Q L t"0Ul L 000 '44 '0"d, ~ 00 Im -q~Q 0% (m. v4 -4 0% 00 M m r-4 -4 0 r-4 0
CU r)-4S -4 r.4
00 000 C 000 >% cd000 00 00a 0 t- rl t ,r-. 4) t '44
4) a 0 OU It)~ m )' m ~ m m m Go o 000000 0
Cad -B zT STRND x - 0 BEN.4ITE-4-4v4 c - 4J I-4
ZU 0 Go
TYPE 81006-2 I81006-2 04'44 0 4) -H
04) 4)0
p4 4.) 0
DATE 00 -e Lt)%0 0 4) v-4U M%0 0 r-on M t4) -y< r1c4"C, 4( 7 C4 004 C404Z
t- 00 -4 -1SHO qt L n. 0Q 0o-t 4 climt Ln r" 00 U UU USHOT V le iJn uu unLnLn uuLntnL
34
-4- -- - -
.8d
CU
.r -4 CU
.f-4
CU4-1 0178 0.~ 0
.04.1
- $40
-4 - $ 4 0d 0) C04 =4HC$ P4 4-1>0 0 4 0 0
a 4) (0- $4 )0n 41-1 (en 0 $49 ,4 4en 00 00 0 0
0) 0 $44
CU 41 u en1 to. *-
V0 0 1: cU 4rC $4-H410 0n 0 XC. 0.
0 00 0 0 o0*.
,4 x a.~C P $ 4 P>n oa go .L .0 4)U
0 $
p4 C~ ~ Q. ~ 35
I- Slight change in
S.slope is alright
Smooth Inflec- Near Step Bump Peak Spike
(clean) tion Step (flat)
C I N F B P s
Figure A-1. Characterization of pressure-time traces.Nomenclature is the same whether the feature occurs on therising or falling side.
ACTUAL CURVE
w!
2nd TIMEFeature
I1st 3rdFeature Feature
Figure A-2. Illustrative example. These features aresuperimposed on the basic one in this example. Thiswould be called "Inflection, peak bump", "IPB" in Table A-1.
36
. ..-..-. . o . . .' . ~ -. .. . . -
The terminal ballistic data tabulation was condensed as much as possibleby tabulating only those items which changed frequently. The rest of thedata is summarized before the tabulation. All of the targets were comprisedof rolled homogeneous armor (RHA) for ammunition testing, meeting MilitarySpecification MIL-S-13812. The target plate hardnesses were, at best,measured by a single Brinnel impression to determine if indeed the materialwas RHA. RHA varies in hardness with thickness within a given range of values.While target hardness definitely influences penetration, the lack of adequatemeasurement of hardness (a proper Brinnell hardness is the average of 20numbers) and the exploratory nature of the shots prompted us to merely reportthe range of check hardnesses experienced for the target thicknesses used andcontrast them with the values in the specification. There is no reason tobelieve that the hardness of the plates checked differs significantly fromthe nominal value in the specification. Table A-2 presents the data.
Table A-2 Specification and check hardness of RHA used in 1981
MIL-S-13812 Check Hardness NumberPlate Specification Average of
Thickness Hardness Range Value Values(mm) (BHN) (BHN)
38 293-331 294 2
51 269-311 289 6
76 269-311 286 2
102 241-277 258 19
152 241-277 235 2
There were three classes of penetrator material used in the year's tests.
Soft steels comprised an unspecified mild steel, AISI S-7 in its as-received
state, or 4340 in its as-received state. The hardness ranged about Rockwell
B 100 or the roughly equivalent Rockwell C 20. There were three shots with
the rods hardened to Rc 53, which is approximately the hardness used for anti-
armor steel long rods. Five shots involved Kennametal W-2*, a tungsten alloy
with good terminal ballistic properties. It was supplied to us by the Army
Materials and Mechanics Research Center (AIMRC), Watertown, MA. The projectile
types are described as a slug in a carrier, a short rod (SR), and a long rod
(LR). The slug was a 38mm diameter soft steel cylinder embedded flush with
the face of a full bore polycarbonate (PC) cylinder that served as a (non-
discarding) sabot and obturator in one. The leneth of the steel slue was ad-justed to give the appropriate in-bore mass. The short rods had a length-to-diameter ratio (L/D) of three, and the long rods, 10. Both had hemispherical
Kennametal W-2 is a trademark of Kennametal Inc., Latrobe, PA.
37
4
noses and flat tails. Where the L/D is different than this, either the rodwas upset and bulged at the end on launch, or the nose snapped off. Theactual length that struck the target was measured from the radiographs and isreported as striking length. The rods were usually only bulged for a shortdistance, so nominal diameters are listed. Several masses were tried in thetwo geometries, but the data is tabulated in the order of increasing L/D first,thickness to diameter ratio (T/D) next, and velocity third, on the assumptionthat isotropic scaling may be used. In the data tabulation, projectile com-ponents are listed in the order in which they were judged to be effective.It is unclear whether the plastic carrier contributed substantially or evensignificantly to penetration. When the carrier is not listed, it separatedfrom the slug in flight and struck well away from the slug.
Various RRA target arrangements were placed in the range, all at 00obliquity. In a number of them, the behind-target x-ray system was being
proofed out be radiographing the projectile in flight, so that the targetswere very close to the butt. In some cases, this interfered with the formationof the bulge or perforation. Only a few radiographs unequivocally show enough
- behind-target debris to measure velocity. No residual penetrator was dis-cernible in any of them. When there was more than one target plate or element(including air space) that participated in the shot performance, these arelisted in order in which they were encountered. In one case, witness plateswere used to measure location, size, and lethality of behind-armor debrisfrom a perforating short rod.
Abbreviations and conventions used in this tabulation that aren't the sameas in the interior ballistic data calculation require explanation. Striking
.- velocity and yaw are taken from the last station before the target at whichthey were measurable. In shots after number 49, the striking yaw and velocitywere extrapolated using average linear velocity decay and yaw growth numbersfrom all radiographic measurements. The figure for critical yaw (discussedin the text) for slugs and short rods was generated by averaging the holediameters for all shots with that rod diameter. On long-rod shots, individualhole diameters were used to compute a critical yaw on each shot, as the longerrods are much more yaw-sensitive. Hole diameters are that of the steady-statechannel. "Splat" indicates a high yaw hit. Deep penetrations sometimes resultin a tapering hole, in which case the dimensions are given in a note. The massloss measured was reported, but, due to the large size of the plates, is notsignificant in most cases where there was no perforation. This is indicatedby a NS entry. Whether or not the pusher disc hit the penetration is answeredwith Y for yes and N for no in the next column, and P stands for partialpenetration (no perforation) and C for complete penetration (perforation) inthe column after that. If there was a partial penetration, the next columnsgive the penetration depth (P) from the location of the entrance surface ofthe target and the bulge height, then the ratio of penetration depth to pro-jectile length (P/L) and to diameter (P/D) to aid in plotting the data indimensionless terms. Where the penetration depth could not be determined fromprobing an empty hole, the target was sawed in half. Where a residual penetra-tor could be recovered from a penetration channel, its length and mass werereported as MR and LR.
38
In the body of the table, figures in parentheses indicate a number thatis meaningless for the reason given in the comments column. Columns bearingan entry C followed by a two digit number refer to comments on the right orbottom of the page. A dash indicates that an individual entry would not beapplicable at that point, and a D prece-ding a depth indicates that only adent was formed (no material was evacuated). In cases where the target platewas heavily bulged, it is possible for the penetration depth to exceed thetarget thickness, without perforation, and still have a significant amount ofmaterial left along the line of fire. Disregards and other shots for whichthe terminal ballistic data is unavailable are not listed. The data is pre-sented in Table A-3.
39
0 41 b4- .CO
00 0 q)
U)00,00 In cisE-. t4 4) oI .- 0 41
a 4 U-4 4- 4) PV00 :3 0 0 4) ' k 00C C
Q Ln - Oz O0 Im 0 11,
U))
z0 -
.0.. A
Ln U
Cd A
4JJ0.
a. LI) . uC C6
00ix~ Uz 9x w 0.0 U ..
00 w000 0 0 0 - r1V4 "
0n L tn 'I n Zn n Zn Z 000M. r4J C4 C1 1 e q
0n OI0 '0 C4 0 CIA1 '
r- - C) r4 - 44 W) 4
mI wI mI U) mI r- 00 U)0 00 W
tj %0) 00 M LI t) %0 M10 M N LID t M Dtno t)0
-4 0 4 eC4 -4 " (N" N -4 C -4 0)j '0t4 -
0 Go 00 00 0o (0 LI) c 0 0 I
~ s1 I) 0 0) 6 (N '00(
q (N i Mv-4 -H 4 (N P- N -HP4 -4 - 4 -4 - r
QI to mtI) tI) LI
-L oU *U .U .y .
0 Q 0 0 0 0 0
~U U U~U~~ ~UU40
uLn un" ItI
le -m w %0 00 (7$ 0.-
-d 0.- 4 $4 on ~
* 0 41
b~C- C#;
4.) r4 10 -0.44.J 0 - M~OCJ
0~ ~ OWr $e.-4 CO
PUSHER z .>.zz
STRIKEo -M In ef(4 ao -4 "-r4 LnOaI-. r-U41C C! 'I 40tf *OCj 0V 4-n
t" 4~o e " 00
u eUd 14m0 tVM lo lI 0 nw
%0 p0
W 4)
m 0 C mDC Cll 0t. O 0 cc mIcte .
00 04
U) N 1 N0 -f 0 n n V- 4v r4r-lv 00cc e '0 % 00O '0 I 4
mU mtr 4mm 16* nL ON C4C4NC. ~ 4(4 lN CIA
'- t le 1'- 0 In 0 00 C le & Ule~ r le 0 U) 4Je C44 V w4 . 4 eq C4 to 4-J4. O
v-44 v-.-tl4
In - 0 QJ 0. 4J 0 0I nI n
NU ucc-4- rM le 1 NC-40 O)OOq0 000 00
-e In 4tn t In~tt tot InCnUUUeVU l -
41 q(D+- A +
U-1
zC'.4 C~4 (7) LI %ON r, JD 00
0 ~ 4
o V-4r-q.m (4 L,)Qr-.('J r - *f %04)
41.
,:t r4 %00 wtf-CJ -4 0 0* ~ f
z 0 n f)r, Ln L ) 0n 00-'
00 4 )0n 0
%-d II -e L
w ~0 0
mO r P r c4coc% c ,- ~ L n)- *f*lCl o41~
4w r t r 0= e omi r- 1,- 000 r'0 qU000 .,-4
coA IIr-u a il i.M.a 0000 'O'0C0.110 OCdI 4-10~~~4 H Neu rNf--r
4J PUSHERlhf M'e4'e4' 00 -4 5go~4-4- +j'. 4 1 ) 4
-0 0~?
000 0000 00044
000 0000 a 0 0 00 0 0 0 0a 0 c
01- - - - -4 -4 -- l 0 " - 4 (
w V42
'4 C; . .
-E-z M0 C
wi r- o W i
000 ~ 0 (X C
4...
0 O0
CA L) 0
4J PUSHER r-SSTRI KE ->> -
.-4 U. 414J (A~- C4 %n c
Cfl Z Z ZZ*
-4E-F- E- E- u.-4 w - rl
-u u~ - .91 Cu "(13(co 00 aaC) 0
Cuu
0j E 1 P4 00 . C
> r= 0 -0ol l(
I CI
qt N % % %
w 0 0
(n 4)4% p r- 44
r= cm .-4I
0tw0 0. 4 4
414-Lr) ~ ~ 'tenL L 0
r4 (14 co
3 V-4 0)4-0 Q 0 0
43-4
qoO
DISTRIBUTION LIST
No. of No. ofCopies Organization Copies Organization
12 Administrator 14 CommanderDefense Technical Info Center US Army Armament ResearchATTN: DTIC-DDA and Development CommandCameron Station ATTN: DRDAR-DCG, BG H. WhittakerAlexandria, VA 22314 DRDAR-TD, Dr. V. Lindner
DRDAR-TDC, Dr. D. Gyorog1 Director DRDAR-TSD, Mr. Fulton
Defense Advanced Research DRDAR-TSS,Projects Agency DRDAR-LC, Dr. J. Frasier
ATTN: Tech Info DRDAR-LCA-M,1400 Wilson Boulevard G. Randers-PehrsonArlington, VA 22209 DRDAR-LCF, G. Demitrack
DRDAR-LCP-T, R. Price1 Director DRDAR-LCU, E. Barrieres
Defense Nuclear Agency DRDAR-SCArlington, VA 22209 DRDAR-SCM, Dr. E. Bloore
DRDAR-SCS-M, R. Kwatnoski1 Deputy Assistant Secreatary Dover, NJ 07801
of the Army (R&D)Department of the Army 2 DirectorWashington, DC 20310 US Army ARRADCOM
Benet Weapons Laboratory2 Commander ATTN: DRDAR-LCB-TL
US Army BMD Advanced Dr. Joseph E. FlahertyTechnology Center Watervliet, NY 12189
ATTN: BMDATC-M, Mr. P. BoydMr. S. Brockway 1 Commander
.RO Box 1500 US Army Armament MaterielHuntsville, AL 35804 Readiness Command
ATTN: DRSAR-LEP-L, Tech Lib1 HQDA (DAMA-ARP) Rock Island, IL 61299
Washington, DC 203101 Commander
1 HQDA (DAMA-MS) US Army Aviation ResearchWashington, DC 20310 and Development Command
.ATTN: DRDAV-E2 Commander 4300 Goodfellow Boulevard
US Army Engineer Waterways St. Louis, MO 63120Experiment Station
ATTN: Dr. P. Hadala 1 DirectorDr. B. Rohani US Army Air Mobility Research
P.O. Box 631 and Development LaboratoryVicksburg, MS 39181 Ames Research Center
Moffett Field, CA 940351 Commander
US Army Materiel Developmentand Readiness Command
4 ATTN: DRCDMD-ST5001 Eisenhower AvenueAlexandria, VA 22333
4S
|7
DISTRIBUTION LIST
No. of No. ofCopies Organization Copies Organization
I Commander 2 CommanderUS Army Communications Research US Army Research Office
and Development Command ATTN: Dr. E. SaibelATTN: DRDCO-PPA-SA Dr. R. WeigleFort Monmouth, NJ 07703 RO. Box 12211
Research Triangle ParkI Commander NC 27709
US Army Electronics Researchand Development Command I Director
Technical Support Activity US Army TRADOC SystemsATTN: DELSD-L Analysis ActivityFort Monmouth, NJ 07703 ATTN: ATAA-SL (Tech Lib)
White Sands Missile Range
3 Commander NM 88002US Army Missile Research
and Development Command 3 CommanderAT- DRSMI-R Naval Air Systems Command
DRSMI-RBL ATTN: AIR-604DRSMI-YDL Washington, DC 20360
Redstone Arsenal, AL 358983 Commander
2 Commander Naval Sea Systems CommandUS Army Tank-Automotive Research Washington, DC 20362
and Development CommandATTN: DRDTA-UL; V. H. Pagano 2 CommanderWarren, MI 48090 Naval Air Development Center,
JohnsvilleCommander Warminster, PA 18974TARADCOM Tank-AutomotiveSystems Laboratory 1 Commander
ATT1 T. Dean Naval Ship Engineering CenterWarren, MI 48090 Washington, DC 20362
I Project ManagerTank Main Armament Systems 2 CommanderATTN: DRCPM-TMA-TM, A. Albright Naval Surface Weapons CenterDover, NJ 07801 ATTN: Dr. S. Fishman
Code U-li, J. R. RenziS Director Silver Spring, MD 20910
US Army Materials and MechanicsResearch Center 3 Commander
ATTN: DRXMR-T, Mr. J. Mescall Naval Weapons CenterF. Quigley ATTN: Code 31804, Mr. M. SmithR. Muldoon Code 326, Mr. P. CordleD. Papetti Code 3261, Mr. T. Zulkoski
DRXMR-ATL China Lake, CA 93555
Watertown, MA 02172
•46
" . . . " " -. " * . * "
.-, : . - . . -' - . . ._--_ . .- .... . - .. , , "- - . . -_ .
DISTRIBUTION LIST
No. of No. ofCopies Organization Copies Organization
3 Commander 1 ASD/XRPNaval Weapons Center Wright-Patterson AFB, OH 45433ATTN: Code 3835, Mr. M. Backman
Mr. R.E. VanDevender,Jr. 10 Battelle Northwest LaboratoriesDr. O.E.R. Heimdahl P.O. Box 999
China Lake, CA 93555 ATTN: G. D. Marr
Richland, WA 99352DirectorNaval Research Laboratory 3 Lawrence Livermore LaboratoryATTN: Dr. C. Sanday P.O. Box 808Washington, DC 20375 ATTN: Dr. C. Cline
Dr. R. Werne1 Superintendent Dr. M. L. Wilkins
Naval Postgraduate School Livermore, CA 94550ATTN: Code 69, P. MartoMonterey, CA 93940 2 Los Alamos Scientific Laboratory
P.O. Box 1663HQ USAF/SAMI ATTN: Dr. R. KarppWashington, DC 20330 Dr. J. Taylor
Los Alamos, NM 875441 AFIS/INOT
Washington, DC 20330 6 Sandia Laboratories
ATTN: Dr. R. Woodfin21 AFATL/DLJM(MAJ G. Spitale, Dr. M. Sears
20 cys) Dr. W. Herrmann(Mr. L. Wilson, 1 cy) Dr. L. Bertholf
Eglin AFB, FL 32542 Dr. A. Chabai
Dr. C. B. Selleck10 AFATL/DLYV(Mr. J. Collins) Albuquerque, NM 87115
Eglin AFB, FL 325421 Director
1 AFATL/DLYV National Aeronautics andEglin AFB, FL 32542 Space Administration
Langley Research Center1 ADTC/DLODL Langley Station
Eglin AFB, FL 32542 Hampton, VA 23365
1 AFATL/CC 1 AAI CorporationEglin AFB, FL 32542 P.O. Box 6767
ATTN: R. L. Kachinski1 AFATL/DLODR Baltimore, MD 21204
Eglin AFB, FL 32542
1 Aerojet Ordnance C'-any1 ASD/ENESS (S. Johns) 9236 East Hall Roaa
Wright-Patterson AFB, OH 45433 Downey, CA 90241
1 ASD/ENFEA 1 Aerospace CorporationWright-Patterson AFB, OH 45433 2350 E. El Segundo Blvd.
ATTN: Mr. L. RubinEl Segundo, CA 90245
47
DISTRIBUTION LIST
No. of No. ofCopies Organization Copies Organization
1 AVCO Systems Division 1 GT Devices201 Lowell Street 5705 A General Washington DriveATTN: Dr. Reinecke ATTN: Niels WinsorWilmington, MA 01887 Alexandria, VA 22312
2 Battelle Memorial Institute 1 General Dynamics
505 King Avenue RO. Box 2507ATTN: Dr. M. F. Kanninen ATTN: J. H. Cuadros
Dr. L. E. Hulbert Pomona, CA 91766Columbus, OH 43201
I BGeneral Electric Company1 Boeing CompanyLa e i e A nuAerospace Division Lakeside AvenueATTN: Dr. N. A. Armstrong ATTN: D.A. Graham, Room 1311Seattle, WA 98124 Burlington, VT 05401
1 Brunswick Corporation 1 President4300 Industrial Avenue General Research CorporationATTN: P. S. Chang ATTN: LibLincoln, NE 68504 McLean, VA 22101
1 Effects Technology, Inc. 1 Goodyear Aerospace Corporation5383 Hollister Avenue 1210 Massilon RoadSanta Barbara, CA 93111 Akron, OH 44315
1 Electric Power Research 1 H. P. White LaboratoryInstitute 3114 Scarboro Road
PO Box 10412 Street, MD 21154ATTN: Dr. George SliterPalo Alto, CA 94303 2 Honeywell, Inc.
Government and AerospaceI Firestone Defense Research Products Division
and Products ATTN: Mr. J. Blackburn1200 Firestone Parkway Mr. K. H. DoeringsfeldATTN: L. E. Vescelius 600 Second Street, NEAkron, OH 44317 Hopkins, MN 55343
1 FMC Corporation 1 Hughes Aircraft CorporationOrdnance Engineering Division ATTN: Mr. W. KeppelSan Jose, CA 95114 MS M-5, Bldg 808
Tucson, AZ 857061 Ford Aerospace and
Communications Corporation 1 Kaman Sciences CorporationFord Road, PO Box A P.O. Box 7463ATTN: L. K. Goodwin ATTN: Dr. P. SnowNewport Beach, CA 92660 Colorado Springs, CO 80933
48
!
"*..
DISTRIBUTION LIST
No. of No. ofCopies Organization Copies Organization
Lockheed Missiles and 1 Drexel UniversitySpace Company Department of Mechanical Engr.
3251 Hanover Street ATTN: Dr. P. C. ChouATTN: Org 5230, Bldg 201 32d and Chestnut Streets
Mr. R. Robertson Philadelphia, PA 19104Palo Alto, CA 94394
1 Southwest Research InstituteLockheed Missiles and Space Department of Mechanical SciencesCompany, Inc. ATTN: Dr. W. Baker
PO Box 504 8500 Culebra RoadATTN: R. L. Williams San Antonio, TX 78228
Dept. 81-11, Bldg 154Sunnyvale, CA 94086 1 University of California
College of EngineeringNew Mexico Institute of ATTN: Prof. W. GoldsmithMining and Technology Berkeley, CA 94720
ATTN: Phil McLain, TERA GroupSocorro, NM 87801 2 University of Dayton Research
InstituteOrlando Technology, Inc. ATTN: Dr. M. D. NagyP.O. Box 855 Mr. D. P. BowerATTN: Mr. J. Osborn 300 College Park Ave.Shalimar, FL 32579 Dayton, OH 45406
Pacific Technical Corporation460 Ward Drive 1 University of DenverATTN: Dr. F. K. Feldman Denver Research InstituteSanta Barbara, CA 93105 ATTN: Mr. R. F. Recht
2390 S. University Blvd.Rockwell International Denver, CO 80210Missile Systems DivisionATTN: A. R. Glaser4300 E. Fifth AvenueColumbus, OH 43216
Systems, Science and SoftwareP.O. Box 1620ATTN: Dr. R. Sedgwick Aberdeen Proving GroundLa Jolla, CA 92037
Dir, USAMSAAUS Steel Corporation ATTN: DRXSY-DResearch Center DRXSY-MP, H. Cohen125 Jamison Lane Cdr, USATECOMMonroeville, PA 15146 ATTN: DRSTE-TO-F
Dir, USAAPGATTN: STEAP-MT-A, Mr. Falcone
Mr. W. Pless, MTDMr. S. Keithely, MTD
Dir, USACSL, Bldg E3516, EAATTN: DRDAR-CLB-PA
?- .' - ; . -_ ' . .. i - . , . -i :_ - .. L • : i . -. ,i .
. .- , . . . , . - : , .
USER EVALUATION OF REPORT
Please take a few minutes to answer the questions below; tear outthis sheet, fold as indicated, staple or tape closed, and placein the mail. Your comments will provide us with information forimproving future reports.
1. BRL Report Number
2. Does this report satisfy a need? (Comment on purpose, relatedproject, or other area of interest for which report will be used.)
3. How, specifically, is the report being used? (Informationsource, design data or procedure, management procedure, source ofideas, etc.)
4. Has the information in this report led to any quantitativesavings as far as man-hours/contract dollars saved, operating costsavoided, efficiencies achieved, etc.? If so, please elaborate.
S. General Comments (Indicate what you think should be changed tomake this report and future reports of this type more responsiveto your needs, more usable, improve readability, etc.)
6. If you would like to be contacted by the personnel who preparedthis report to raise specific questions or discuss the topic,please fill in the following information.
Name:
Telephone Number:
Organization Address:
FOLD HERE .
Director Ii111NO POSTAGE
US Army Ballistic Research Laboratory INECESSARYIAbede PI I HLED
Abeden rovngGrund M 200 IN THE IUNITED STATES
OFFICIAL BUSINESS
PENALTY FOR PRIVATE UBE, 6300 BUSINESS REPLY MAIL _
FIRST CLASS PERMIT NO 12062 WASHINGTONOC
POSTAGE WILL BE PAID BY DEPARTMENT OF THE ARMY
DirectorUS Army Ballistic Research LaboratoryATTN: DRDAR-TSB -SAberdeen Proving Ground, MD 21005
FOLD HERE