Military

7.62 mm Versus 5.56 mm - Does NATO 
Really Need Two Standard Rifle Calibers
CSC 1986
SUBJECT AREA General
TITLE:  7.62 mm Versus 5.56 mm - Does NATO Really Need Two
Standard Rifle Calibers?
I.    Purpose: To reestablish the 7.62mm NATO cartridge as the
optimum rifle caliber ammunition for the U. S. and NATO.
II.   Problem:  NATO recently adopted the 5.56mm as its second
standard rifle caliber cartridge.  As a result, the existing NATO
standard, the 7.62mm, has been relegated to a secondary 
supporting role within NATO's armed forces.  Although the
selection of the 5.56mm was based on extensive testing, research,
and documented battle performance, this intermediate power round
is not the optimum ammunition and caliber for U. S. and NATO
forces in the contemplated battlefields of the future.
III.  Discussion:  Proponents of the intermediate power 5.56mm
have continuously compared their smaller cartridge to the large
full power 7.62mm.  The results of these comparisons purportedly
show the superiority of the smaller ammunition in the areas of
penetration, lethality, weapon portability, and fire power.
Careful examinaton of these tests and the touted advantages of
the 5.56mm, however, shows that the 7.62mm is still potentially
superior to the smaller round.  For example, in the NATO tests,
researchers have compared a modern, semi-armor piercing round of
ammunition (5.56mm) against a standard ball cartidge
(7.62mm) that has not been improved since its adoption in 1953.
An improved 7.62mm NATO, using the same technology as the
5.56mm, would definitely out-perform the smaller cartridge.  With
respect to portability, second generation 7.62mm rifles are
smaller, more compact, and very comparable to certain 5.56mm
weapons.  Concerning fire power, any full automatic fire with
light assault rifles, even with the low-recoil 5.56mm, is not
effective and only results in a waste of ammunition.  In 
addition, new tecnological developments in body armor may soon
defeat the penetration capability of the small 5.56mm.  New
developments in optical sighting equipment will soon increase
battlefield engagement ranges and thereby exceed the long range
accuracy capability of the smaller 5.56mm.  The large case and
projectile of the 7.62mm, however, are more than sufficient to
accept significant improvements in penetration, lethality, and
long range performance.  This will allow the 7.62mm to remain
effective on futrure battlefields.
IV.   Conclusion:  The 5.56mm will, at best, only be an interim
NATO standard.  Due to its small size, further improvements of
the 5.56mm will be insufficient to keep up with the changing
requirements of future battlefields.  Overall, the older 7.62mm
NATO is a better standard cartridge since it has the capacity and
the flexibility to be significantly improved and thereby remain
effective.
V.    Recommendations:  The 7.62mm NATO cartridge should be
developed with current technology to improve its penetration,
lethality, and overall-performance.  Modern weapons systems
should be further developed to utilize the 7.62mm.  No, NATO does
not need two standard rifle calibers.
Major Vern T. Miyagi                  Conference Group 6
		      RESEARCH PAPER
			    Title
7.62mm Versus 5.56mm - Does NATO Really Need Two Standard Rifle
Calibers?
			   Thesis Statement
    Although the selection of the 5.56 x 45mm cartridge was
based on extensive testing, research, and documented battle
performance, this intermediate power round is not the optimum
ammunition and caliber for U. S. and NATO forces in the
contemplated battlefields of the future.
  I.   Significance of the Controversy
       A. Thesis statement
       B. Method of analysis
  II.  Evolution of the Intermediate Power Cartridge Concept
       A. Germany
       B. Soviet Union
       C. United States
 III.  Development of the Two Standard NATO Cartidges
       A. 7.62 x 51mm NATO
       B. 5.56 x 45mm NATO
       C. NATO trials
       D. Concepts of employment - NATO
  IV.  Comparison of the 7.62mm With the 5.56mm
       A. Physical characteristics and ballistics
       B. Penetration
       C. Portability and weight
       D. Firepower
   V.  Analysis
       A. Problems with the NATO comparisons and tests
       B. Factors not considered in the NATO tests
       C. Effects of technological advances in optical sights and
body armor on the initial imtermediate power concepts
       D. Potential for improvement and development - 5.56mm v.
7.62mm
       E. Lethality of improved round is reduced
       F. Potenial ineffectiveness on NATO scenario battlefields
7.62 mm Versus 5.56 mm - Does NATO Really Need Two Standard Rifle
Calibers?
    On 28 October 1980, after more than four years of extensive
testing at the German Infantry School at Hammelburg, Federal
Republic of Germany, the NATO Small Arms Test Control Commission
(NSMATCC) appoved the standardization of a second rifle caliber
cartridge.  The cartidge selected was the intermediate power
5.56 x 45mm (.223 Caliber) and the improved Belgian version, the
SS109, was selected as the basis for standardization.1  As a
result, NATO now has two standard rifle caliber cartridges, the
full power 7.62 x 51mm NATO (.308 Caliber), in service since
1953, and the new intermediate power 5.56 x 45mm NATO adopted in
1980.  Although the selection of the 5.56 x 45mm cartridge was
based on extensive testing, research, and documented battle per-
formance, this intermediate power round is not the optimum ammu-
nition and caliber for U. S. and NATO forces in the contemplated
battlefields of the future.  Let's examine the concept of inter-
mediate power rifle ammunition, the evolution of the two standard
NATO rifle cartridges, their advantages and disadvantages, and
discuss why the older, full power 7.62 x 51mm NATO cartridge can
better satisfy the present and future tactical needs of the
individual NATO rifleman.
    The concept of intermediate power rifle cartridges began in
Germany prior to World War II.  The standard German rifle car-
tridge used since 1888 was the full power 7.92 x 57mm which
propelled a 198 grain bullet at a muzzle velocity of 2,550 feet
per second (fps) or 773 meters per second (mps).  Comprehensive
studies of the actual distances over which rifle fire was em-
ployed and of the marksmanship capabilities of the average German
infantryman, especially during the heat of battle, convinced
German researchers that a smaller, substantially less-powerful,
and lighter cartridge would be more than adequate.  In addition,
the adoption of smaller intermediate power cartridges would allow
the development of shorter and lighter rifles, the ability to
carry more rounds of ammunition, and the enhancement of accuracy
due to lighter recoil.  German research for a new intermediate
round commenced in 1934, and in 1938 a new intermediate cartridge
was adopted and designated the 7.9 mm Infanterie Kurz Patrone
(7.9 mm Kurz).  This cartridge propelled a small 125 grain bullet
at a relatively moderate muzzle velocity of 2,100 fps (636 mps),
Paralleling the evolution of the 7.9 mm Kurz was the development
of a new, compact, select-fire rifle chambered for the new ammu-
nition.  In 1940, two designs were accepted for field testing and
were extensively used on the Russian front.  The final version
"Sturmgewehr" or assault rifle, the MP43, was adopted in 1943 and
significant numbers were produced prior to the end of the war.
This weapon utilized a thirty round magazine and could provide
both semiautomatic and full automatic fire.  Althought the MP43,
with a fully loaded thiry round magazine, was more than three
pounds heavier than the standard bolt-action Kar 98k rifle, the
new weapon's performance in the field was excellent due to the
terrific firepower now available to the German infantryman.2
    The effectiveness of the new rifle and ammunition did not go
unnoticed by Soviet forces, especially since they were the  first
recipients of its firepower.  Captured rifles and ammunition were
carefully studied, and in 1943 an intermediate power cartridge
designed by Soviet engineers, N. M. Elizarov and B. V. Semin, was
adopted by the Soviet Union.  This cartridge was designated the
7.62 x 39mm Model 1943 and consisted of a 125 grain bullet with a
muzzle velocity of 2,200 fps (667 mps).  Due to wartime materiel
and production shortages, the first weapon designed to use this 
new ammunition, the SKS Carbine, was not adopted until 1946.  One
year later, the famous AK-47, designed by M. Kalashnikov, was
formally adopted by the Soviet armed forces.3  In 1974, a product
improved version of the same basic design, the AKS74 rifle, was
adopted by the Soviet army.  The AKS74 is chambered for a new 5.45
x 39mm (.221 Caliber) cartridge, very similar to our own 5.56 x
45mm NATO.  The Soviets also adopted, at the same time, a new
5.45mm squad automatic weapon, called RPK74.4  These recent
changes in Soviet small arms development are very important
because they closely parallel the small arms concepts of the
U. S. and NATO.
    Like the Germans and Soviets, the U. S. also experimented
with intermediate power cartridges during World War II.  Designed
as a replacement for the pistol and submachine gun during World 
War II, the U. S. .30 Caliber M1 and M2 carbines fires lighter
and smaller .30 caliber cartridges (7.62 x 33mm).  This cartridge
propelled a small round-nosed 115 grain bullet at an initial
velocity of 1,970 fps (597 mps).  The carbine and its cartridge,
however, were designed for issue only to officers, non-commis-
sioned officers, service troops, and members of heavy weapons
crews.  The carbine, with its intermediate power cartridge, was
never designed to replace the M1 Garand and its full power .30
Caliber M2 (30-06) ammuntion.  Over six million carbines were
produced during World War II and the Korean War.  Although the
carbines were light, compact, had a select fire capability (M2
model), and utilized magazines with capacities of thiry or
fifteen rounds, these weapons eventually came to be unpopular
with U. S. troops due to the limited range and inadequate stop-
ping power of the carbine ammunition.  Soon after the Korean War,
the U. S. M1 and M2 Carbines were retired from service.5
    Such was the evolution of the intermediate power cartridge
concepts in Germany, the Soveit Union, and the United States
during the 1940's.  Lets now take a look at the development of
the 7.62 x 51mm NATO and the 5.56 x 45mm NATO during the 1950's
and 1960's
    The first standard NATO cartridge, the 7.62 x 51mm NATO, was
developed by the United States as a successor to the .30 Caliber
M2 round (30-06), which had served as the standard U. S. rifle
cartridge since 1906.  The .30 Caliber M2 cartridge propelled a
150 grain projectile at a muzzle velocity of 2,800 fps (848 mps)
and served the U. S. very effectively in the 1903  Springfield and
M1 Garand service rifles, the Browning automatic rifle, and the
heavy and light models of the Browning machine guns.  Although
the M1 Garand was very effective and highly praised during its
service as the standard U. S. rifle in World War II and Korea,
many infantrymen desired a lighter weapon with greater ammunition
capacity and a select-fire capability.6  Many soldiers attemped
to use the M2 carbine as a replacement for the M1 Garand, but
this proved unsatisfactory due to the inadequate power of the
carbine ammuniton.  In September 1945, after conducting prelimi-
nary tests to improve the M1 rifle, the U. S. Ordnance Technical
Committee turned its attention to the development of a new and
lighter rifle cartridge that would replace the .30 Caliber M2
round.  This interest in a new cartridge was influenced by the
battlefield success of the German 7.9mm Kurz, and Soviet adop-
tion of their Kalashnikov light assault rifles using the new 7.62
x 39mm Model 43 intermediate power ammunition.  As the develop-
ment of the new U. S. service rifle cartidge progressed, however,
traditionalism took hold as U. S. Army participants began to feel
that the intermediate power ammuniton, used by the Soviets and
the Germans, were too limited in their effective combat ranges
and power to satisfy U. S. infantry requirements.  The result was
a compromise.  The Ordnance Technical Committee came up with a
shortened version of the old .30 caliber M2 cartidge.  This new
cartridge, designated the 7.62 x 51mm T65, was not an inter-
mediate power round.  Although shorter by a half inch than the old
Caliber .30 M2 round, it still propelled a 147 grain bullet at a
muzzle velocity of 2,800 fps (848 mps) -- essentially identical
to the old .30 Caliber M2 round.  Newly developed ball powder
allowed the use of smaller cartridge case to produce pressures
and velocities identical to the old full power .30 Caliber M2
round.7
    Final U. S. adoption of the new 7.62 x 51mm T65 cartridge
depended upon the acceptance of the new round by members of the
NATO alliance. During the early 1950's, the British conducted
their own tests to determine the optimum rifle ammunition for
their troops.  They concluded that a .280 Caliber (7 mm)
cartridge was the ideal rifle caliber.  The proposed British
cartridge was a true intermediate power cartridge based on German
experience and Soviet developments.  In 1953, after much
political debate, the U. S. 7.62 x 51mm T65 round was finally
adopted by the NATO Alliance as its standard rifle caliber
cartidge.  In 1957, after numerous trails, the U. S. finally
adopted the M14 rifle as its new standard 7.62mm NATO caliber
service rifle.  The other members of NATO adopted either the
German G3 or the Belgian FN FAL as their standard 7.62mm NATO
caliber service rifles.8
    The 5.56 x 45mm cartridge and the M16 rifle was originally
developed and unilaterally adopted by the United States in 1963
for initial employment in Southeast Asia.  A resurgence of U. S.
interest in intermediate power rifle cartridges developed soon
after the 7.62 x 51mm NATO was adopted in 1953.  A series of
tests, commissioned by the U. S. Army and conducted by the Opera-
tions Research Organization (ORO), concluded that the rifle was
seldom used effectively by U. S. troops at ranges in excess of
300 meters (330 yds).  This conclusion was based on studies of
actual battles involving U. S. soldiers.  According to the ORO
studies, the inability of U. S. soldiers to effectively engage
targets beyond 300 meters was due to their inability, under
battle conditions, to see and identify targets beyond that
range.9  The ORO studies, however, failed to consider whether the
enemy targets were behind heavy brush, or barriers such as
sandbags, dirt berms, and coconut logs when fired on by U. S.
soldiers.  The study assumed that there was nothing between the
firer and the target to impede the flight of the rifle projec-
tile.  Concurrently, ballistic experiments, conducted as part of
the U. S. Army Project Caliber, demonstrated the small high
velocity bullets, ranging in caliber from .222 to .257 inches and
weighing only 40 to 55 grains, were very effective at ranges up
to 400 meters.10  As a result of these studies, the Continental
Army Command (CONARC) asked selected commercial arms organiza-
tions to develop high velocity .223 Cal (5.56mm) ammunition and
light weight assault rifles chambered for them.  After extensive
testing of candidate weapons and ammunition submitted by various
manufacturers, CONARC selected the AR15 rifle and the 5.56 x 45mm 
ammunition, both developed by Eugene Stoner of the Armalite
Division of the Fairchild Aircraft Engine Corporation.  The 5.56
x 45mm cartidge was derived from the .222 Remington and .22
Hornet commercial cartridges used by small game hunters
throughout the United States.  After some modifications for mili-
tary use, the AR15 and its 5.56 x 45mm, cartridge were accepted by
CONARC and designated as the M16 and the M193, respectively.11
The M193 cartridge, as finally accepted by CONARC, propelled a
small 55 grain bullet at an inital velocity of 3,180 fps (964
mps) through the standard 20 inch barrel of the M16.  Test
weapons and ammunition were sent to Southeast Asia in 1962 for
combat field analysis.  The reports from both U. S. and allied
forces were very good and consequently, in 1963, Secretary of
Defense McNamara ordered the cessation of M14 production and
announced the purchase of 85,000 M16 rifles for the Army and
19,000 for the Air Force.  Subsequent performance of the M16 in
Vietnam was marred by frequent jamming caused by improper and
insufficient maintenance in the field.  Performance quickly im-
proved as chrome barrels and chambers were used in the newer
M16A1 model, and proper maintenance procedures were employed by
troops in the field.  The U. S. finally had adopted an inter-
mediate power fifle cartridge and a true light-weight assault
weapon to use it.12
    The adoption of the 5.56 x 45mm cartridge and the M16 rifle
put the U. S. into the situation of having two standard service
rifles.  The initial U. S. Army employment concept called for the
issue of the M16 to special operations and airborne troops, and
to troops in Southeast Asia.  The M14 would still be issued to
troops stationed in Europe of assigned to NATO.13  This initial
concept proved to be logistically impractical and, eventually,
all U. S. troops were issued the new M16 rifle and 5.56 x 45mm
ammunition.
    Based on the overall success of the 5.56mm ammunition in
Southeast Asia, after the initial problems with the M16 were
solved, other nations began to produce assault type rifles using
the U. S. 5.56 x 45mm ammunition.  In order to standardize the
use and procurement of 5.56mm ammunition among member nations,
NATO commenced formal adoption trials for a second small rifle
caliber cartridge in 1976. The Belgian product-improved version
of the U. S. M193 5.56 x 45mm cartridge was adopted by the
alliance in 1980.
    The current NATO concept of employment calls for the issue
of the 5.56mm weapons to individual riflemen, members of crew-
served weapon teams, support troops, and officers and NCO's.  The
current NATO concept also includes the development and adoption 
of a squad automatic weapon (SAW) in 5.56 x 45mm NATO caliber.
The goal of NATO small arms employment is to ensure ammunition
interchangeability at the basic infantry squad level.  The full
power 7.62 x 51mm NATO remains the standard ammunition for the
heavier belt-fed medium machine guns (M60, MG3, and FN MAG)
employed with infantry weapons squads, weapons platoons, and as
vehicle mounted support weapons.14  In addition, specialized
sniper weapons still employ the longer ranged 7.62 x 51mm NATO.
     The foregoing paragraphs reviewed the evolution of the
intermediate  power cartridge concept, documented the development
of the two standard NATO cartidges, and discussed the current
concept of employment within the NATO alliance.  Let's now compare
the two cartidges, examine their strengths and weaknesses, and
analyze why the 7.62 x 51mm NATO is a better rifle cartridge in
the long run for the U. S. and NATO (Table I).
     The current production 7.62 x 51mm NATO ball cartridge has
remained unchanged since its adoption by NATO in 1953.  As typi-
fied by the U. S. M80 ball and the Belgian M77 ball, this
cartridge propels a 147-grain cupronickel-jacketed lead bullet
at a muzzle velocity of 2,800 fps (848 mps).  Total cartridge
length and weight are 2.80 inches and 386 grains, respectively.15
Utilizing a standard 22-inch barrel with a rifling twist of one
turn in twelve inches (M14 rifle), the maximum effective range of
the 7.62 x 51mm ball cartridge is listed as 620 meters (682
yds).  The U. S. M80 and the Belgian M77 ball projectiles can
penetrate the standard NATO 3.45 mm (.14 inch) thick steel plate
up to a range of 620 meters, and can penetrate one side of the 
U. S. steel helmet up to a range of 800 meters (880 yds).16  In
barrier and fortification penetration tests, the 147 grain ball
projectile can consistently penetrate two test building blocks.17
     The SS109 5.56mm NATO cartridge is a second generation
intermediate power round developed with 1970's technology.  It is
significantly more powerful and effective than the U. S. M193
5.56mm ball round originally used with the M16 rifle.  The new
SS109 cartridge propels a heavier 62-grain semi-armor piercing
projectile at an initial velocity of 3,050 fps (924 mps).18  The
improved projectile contains a 10-grain .182 caliber hardened
steel penetrator that ensures penetration at longer ranges.
Total cartridge length and weight are 2.26 inches and 182.0
grains, respectively.  The increased length and weight of the new
SS109 projectile requires a faster rifling twist of one turn in
seven inches to fully stabilize the new projectile in
flight.19  The predecessor M193 5.56mm, which used a projectile
weighting only 55 grains, was only marginally stabilized with a
slower rifling twist of one turn in twelve inches.  The new
projectile can penetrate the standard NATO 3.45mm steel plate up
to a range of 640 meters (704 yds) and one side of the U. S. 
steel helmet up to a range of 1,300 meters (1430 yds).20  In tests
of barrier and fortification penetration however, the steel
penetrator of the SS109 could not pierce any of the test building
blocks.21
     The primary advantages of the intermediate power 5.56 x 45mm
NATO cartidge are summarized as follows: (1) the penetration and
power of the SS109 version are superior to the 7.62mm NATO and
more than adequate for the 300-meter average combat range
documented in actual battle (ORO studies): (2) the lower recoil
generated by the 5.56mm cartridge allows more control during full
automatic fire and therefore provides greater firepower to the
individual soldier; (3) the lesser weight of the 5.56mm
ammunition allows the individual soldier to carry more ammunition
and other equipment; (4) the smaller size of the 5.56mm
ammunition allows the use of smaller, lighter, and more compact
rifles and squad automatic weapons and; (5) the lethality of the
5.56mm projectile is greater than the 7.62mm projectile at normal
combat ranges, due to the tendency of the lighter projectile to
tumble or shatter on impact.  In summary, the 5.56mm NATO
provides greater firepower and effectiveness than the larger and
heavier 7.62mm NATO.  This concept of more for less appears very
convincing, however upon careful analysis, this idea loses its
credibility.  Let's examine each of the advantages of the 5.56mm
NATO, compare them to the qualities of the larger 7.62mm NATO,
and discuss some critical factors not addressed by proponents of
the smaller cartridge.
     The penetration results obtained by the  NSMATCC with the
5.56mm SS109 cartridge are impressive.  The SS109 can penetrate
the 3.45mm standard NATO steel plate to 640 meters, while the
7.62mm ball can only penetrate it to 620 meters.  The U. S. steel
helmet penetration results are even more impressive as the SS109
can penetrate it up to 1,300 meters, while the 7.62mm ball cannot
penetrate it beyond 800 meters.  These comparisons however, do
not consider the fact that the SS109 uses a semi-armor piercing,
steel-cored projectile, while the 7.62mm ball uses a relatively
soft anti-personnel, lead-cored projectile.  A semi-armor
piercing 7.62mm caliber projectile, using second generation
technology as the SS109, would easily out-perform the smaller
SS109 projectile in penetration tests at all ranges.22  With
respect to barrier and fortification penetration tests, the
7.62mm ball projectile can consistently penetrate two test
building blocks, while the SS109 semi-armor piercing projectile
cannot penetrate a single block.  In light of these
considerations, the idea of SS109 penetration superiority over
the 7.62 x 51mm is not valid.
    The concept that greater firepower can be achieved by provi-
ding as much infantrymen with a full automatic fire capability is
not realistic.  Battle experience has shown that full automatic
fire from light assault rifles is largely ineffective and only
resutls in the expenditure of large quantities of ammunition.
Even with the lower recoil generated by 5.56mm ammunition, auto-
matic fire dispersion is still too large to be effective.23  Fire
power is normally equated with maximum "steel" on target, not with
maximum steel in the general direction of the target.  Full
automatic fire with the 5.56mm NATO just as wasteful and
Confirming this view is the fact that second generation assault
rifles, such as the U. S. M16A2 and Belgian FN FNC, are not
employing a 3-shot burst control in lieu of a full automatic
capability.24  With this burst control feature, a thirty round
magazine produces only ten bursts.  Do we need thirty rounds to
successfully hit and incapacitate ten enemy targets?  Even with
3-shot burst control and the lower impulse of the 5.56mm
ammunition, shot dispersion is still too large to be effective.
Perhaps a single well-aimed 147 grain 7.62mm bullet would have
more effect than three rounds of 5.56mm fired in the burst 
control mode.  As a result, the lower recoil and impulse of the
5.56mm ammuntion does not provide greater fire power since full
automatic fire from an individual assault rifle is largely
ineffective and only wastes ammunition.
     A great deal of emphasis has been placed, during the
development of intermediate power ammunition, on ammunition
weight.  It is a fact that 5.56-mm NATO ammunition weight only
47% as much as 7.62 mm NATO ammunition.  This weight reduction
advantage however, comes with a corresponding disadvantage in the
power and effectiveness of the ammuntion.  The 5.56mm NATO
cartridge was originally derived from commercial small game and
varmint cartridges used by hunters throughout the United States.
In most States, the .223 Remington cartridge, the commercial
version of the 5.56 x 45mm NATO, is outlawed for use against
deer-sized or larger game.  This restriction even includes the
explosive hollow-point versions using 68-grain projectiles.
Years of hunting experience has shown that the small 5.56 x 45mm
cartridge is incapable of consistently stopping deer-sized or
larger game.  Consequently, this cartridge is limited to game
such as woodchucks, gophers, turkeys, and prairie dogs.25  Is
this cartridge really adequate for human-sizes targets?
Soldiers can definitely carry more 5.56mm ammunition, but will
they be carrying more effective ammunition?  As a case in point,
battle experience in the Philippines, between government troops
(armed with the 5.56mm M16A1) and Communist rebels (armed with
vintage .30 Caliber M1 Garand and Browning automatic rifles), has
shown that the greater penetration capability of the older full
power cartridge gave the rebels superior effective firepower.26
     Another stated advantage of the smaller 5.56mm NATO
cartridge concerns the employment of shorter and lighter weapons.
Current versions of the Israeli Galil and FN FAL Paratroop rifles,
however, both in 7.62mm caliber, weigh only nine to ten pounds
fully loaded with twenty-round magazines.  These 7.62mm NATO
weapons also have shorter barrels and folding stocks that make
them very compact.  The new U. S. M16A2 and the new Belgian FN
FNC, both second generation 5.56mm NATO assault rifles, weigh
approximately eight27 and ten pounds,28 respectively, when fully
loaded with thirty-round magazines.  The purported reductions in
weight and improvements in compactness are really not significant.
     The lethality of the original M193 5.56mm projectile is
awesome, at ranges under 200 meters, due to the tendency of the
marginally stable 55-grain bullet to tumble or shatter on impact
with any target.  Lethality of the M193 5.56mm projectile beyond
200 meters, however, falls very sharply as range increases and
velocity decreases.29  The lethality of the new SS109 5.56mm
projectile on the battlefield is questionable.  The SS109
projectile is longer and heavier than the M193 projectile and is
more stabilized in flight with the faster rifling twist used in
second generation assault rifles.  The emphasis, in the develop-
ment of te SS109 projectile, was to increase stability and
therefore penetration at longer ranges.  The increased flight
stability of the new SS109 projectile does effectively enhance
penetration at longer ranges, but this same stability reduces the
projectile's tendency to tumble or shatter upon target im-
pact.30  As a result, the emphasis on penetration in the new
SS109 projectile may result in a sharp decrease in lethality, as
compared to its predecessor M193 cartridge.
     The adoption of intermediate power ammuntion by a large
number of countries was based on the limited ability of the
average soldier to discern and identify targets under battle
conditions.  The U. S. Army's ORO studies during the 1950's,
confirmed these ideas and established 300 meters as the practical
range limit for rifles under battle conditions.  The ORO studies,
however, failed to consider the technological advances of the
1970's and 1980's in the area of optical weapons sights.  The
battle proven British Trilux optical sight, with a four power
magnification, has been employed by the British effectively on
their 7.62mm FN FALs for many years.31  Their newly adopted 5.56mm
NATO individual weapon, the SA 80, utilizes a built-in version of
the Trilux called the SUSAT.32  The Austrian developed 5.56mm
NATO assault rifle, the AUG, employs a 1.5 power optical sight
built in to the weapon's carrying handle.33  The U. S. Army is
also considering a new optical sight for its version of the 
M16A2.  These improved optical sights greatly increase the
average soldier's ability to see and identify enemy targets at
longer ranges.  As the soldier's ability to engage targets beyond
the 300 to 400 meter NATO limitation increases, the long range
accuracy limitations of the 5.56mm SS109 projectile will become
evident.  The 62-grain 5.56mm NATO projectile is significantly
more affected by weather conditions than the heavier projectile
of the 7.62mm NATO.  For example, at 400 meters the required
windage adjustment for a 10 mph crosswind for the SS109 cartridge
is approximately 9 clicks into the wind using the M16A2 sights.
Under the same conditions, the required windage adjustment for
the 7.62mm NATO cartridge is only 4 clicks using the M14 sights.
The larger sight adjustment, required for the SS109 projectile,
produces a greater margin of error that increases as distance
increases.  As the potential rifle engagement distances
increase, due to improvements in optical sights, the limited
accracy potential of the small 5.56mm NATO projectile will
severely limit any benefits that may be derived from such optical
improvements.
     New technological developments in body armor and individual
protection, such as kevlar and other light-weight ceramic and
composite armor, may soon defeat the penetration capability of
the small 5.56mm SS109 projectile.  For example, the new Soviet
5.45 x 39mm ammunition cannot now penetrate a relatively light
5.8 pound flak jacket composed to Kevlar and a 4.8mm (.19 inch)
sheet of hardened steel plate, even at point blank range.34  The
SS109 however, with its steel penetrator still has this
capability.  The primary question is how long will the 5.56mm
SS109 retain this capability?  As a second generation
intermediate power cartridge, further improvements in the small
5.56mm SS109 may not be sufficient to defeat new technological
developments in body armor.  The 5.56mm SS109 projectile is too
small for much significant improvement.
     It has also been maintained, by intermediate caliber propo-
nents, that the 5.56 x 45mm cartridge has proven itself in battle
since its adoption by the U. S. in 1963.  In most of these
conflicts, however, the 5.56mm weapons were employed against
opponents armed with Soviet weapons also using intermediate power
ammunition.  When the 5.56mm weapon comes up against an opponent
armed with weapons using full-power ammunition, such as in the
Philippine example cited previously, the 5.56mm armed soldier
finds himself at a severe disadvantage.
     The "obvious" advantages of the 5.56 x 45 mm NATO are not
obvious at all.  The SS109 is a definite improvement over the
first generation M193 cartridge however, at best it will serve
only as an interim standard.  As technological improvements in
optical sights extend the practical engagement distances for
rifle fire, and as improvements in body armor require greater and
greater power from the rifle cartridge, the SS109 and other
5.56mm caliber ammunition will have to give way to improve and
more powerful ammunition, such as the 7.62mm NATO.  The 7.62 x
51mm NATO has not been improved or modified since its adoption by 
NATO in 1953.  This larger cartridge has a greater capacity for
growth and technological improvement and should be developed to
its potential now.  The large size of the 147-grain 7.62 mm
projectile is more than sufficient to incorporate significant
improvements in lethality and penetration.  We must capitalize on
the Soviet trend toward their 5.45mm caliber weapons by improving
our full power 7.62mm NATO ammunition and designing better and
more efficient weapons to use it.  We have a chance to totally
outclass Soviet small arms in the area of individual and squad
weapons.  Let's do it by upgrading the existing 7.62 mm NATO to
its full potential.
     During the years just prior to World War II, the  Imperial
Japanese Army replaced their 6.5mm (.256 Caliber) rifle ammuni-
tion with a 7.7mm (.303 Caliber) cartridge due to the smaller
round's poor lethality and its inability to penetrate barriers
and effectively stop enemy troops.  During the same period, the
Italians replaced their 6.5mm rifle ammunition with a 7.35mm
(.301 Caliber)  cartridge for the same reasons.  Lets learn from 
their examples and concentrate now on the development and
improvement of the 7.62mm NATO round.  No, NATO does not need
two standard rifle caliblers.
Click here to view image
			Footnotes
     1Edward C. Ezell, Small Arms of the World, 12th Revised
Edition (Harrisburg: Stackpole Books, 1983) Pp. 57,61.
     2IBID, Pp. 514 - 519.
     3IBID, Pp. 34 - 35.
     4Andrew C. Tillman, "IDR Test Fires the AKS74,"
International Defense Review, October 1983, Pp. 1427 - 1428.
     5Edward C. Ezell, Small Arms of the World, 12th Revised
Edition (Harrisburg: Stackpole Books, 1983) Pp. 779 - 784.
     6Edward C. Ezell, The Great Rifle Controversy (Harrisburg:
Stackpole Books, 1984) P. 41.
     7IBID, Pp. 57 - 61.
     8IBID, Pp. 92 - 103.
     9Norman Hitchman, Operational Requirements For An Infantry
Hand Weapon (Chevy Chase: Operations Research Office - The John
Hopkins University Publications, 1952) Pp. 2 - 3.
    10William C. Benjamin Jr.  and Joseph Dubay, The Effect of
Rifle Caliber and Muzzle Velocity on Experimental Probabilities
of Hitting as Obtained from Project Caliber (Aberdeen: Ballistic
Research Laboratories Report No. 964, 1955) Pp. 29 - 30.
    11Edward C. Ezell, The Great Rifle Controversy (Harrisburg:
Stackpole Books, 1984) P. 172.
    12IBID, P. 192
    13IBID, P. 195.
    14Herman Van Assche, "Small Arms and Their Ammunition - The
NATO Competition, "NATO's Fifteen Nations, August - September,
1981, Pp. 92-93.
    15R. T. Huntington, Small-Caliber Ammunition Identification
Guide Vol 1 (Army Material Development and Readiness Command,
Foreign Service and Technology Center, June 1978) Pp. 32.
    16Pierre Crevecoeur, "The Belgian SS-109 Round - Baseline
for NATO's Second Caliber Ammunition,"  International Defense
Review, March 1981, P. 302.
    17Andrew C. Tillman, "IDR Tests the M16A2 Assault Rifle,"
International Defense Review, September 1984, P. 1353.
    18IBID, P. 1353
    19Edward C. Ezell, Small Arms of the World, 12th Revised
Edition (Harrisburg: Stackpole Books, 1983) Pp. 59-60.
    20Pierre Crevecoeur,  "The Belgian SS-109 Round - Baseline
for NATO's Second Caliber Ammunition,"  International Defense
Review, March 1981, P. 302.
    21Andrew C. Tillman, "IDR Tests the M16A2 Assault Rifle,"
International Defense Review, September 1984, P. 1353.
    22Edward C. Ezell, "NATO Small Arms Debate," International
Defense Review, March 1981, P. 297.
    23Andrew C. Tillman, "IDR Tests the M16A2 Assault Rifle,"
International Defense Review, September 1984, P. 1352.
    24Edward C. Ezell, Small Arms of the World, 12th Revised
Edition (Harrisburg: Stackpole Books, 1983) Pp. 64, 255.
    25Jack S. Chase, "Are We Arming American Soldiers to Flight
an Army of Woodchucks?"  Armed Forces Journal International,
October 1981, Pp. 24 - 26.
    26Interview with LTC Wenceslao Cruz, Philippine Marine
Corps, March 3, 1986.
    27Andrew C. Tillman, "IDR Tests the M16A2 Assault Rifle,"
International Defense Review, September 1984, P. 1351.
    28Edward C. Ezell, Small Arms of the World, 12th Revised
Edition (Harrisburg: Stackpole Books, 1983) P. 255.
    29Andrew C. Tillman, "IDR Test the M16A2 Assault Rifle,"
International Defense Review, September 1984, P.  1353.
    30Edward C. Ezell, Small Arms of the World, 12th Revised
Edition (Harrisburg: Stackpole Books, 1983) P. 60.
    31W. J. G. Hancock, "The TRILUX Infantry Sight Unit,"
International Defense Review, April 1973, Pp. 113 - 114.
    32Edward C. Ezell, Small Arms of the World, 12th Revised
Edition (Harrisburg: Stackpole Books, 1983) Pp. 298 - 301.
    33IBID, P. 223.
    34Andrew C. Tillman, "IDR Tests the AK74," International
Defense Review, October 1983, Pp 1429 -1430.
    35Edward C. Ezell, Small Arms of the World, 12th Revised
Edition (Harrisburg: Stackpole Books, 1983) P. 603.
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2.  Chase, Jack S.  "Are We Arming American Soldiers to Fight an
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