MODERN ARMAMENT.
THE ARTILLERY OF A FIELD ARMY; ITS FUNCTIONS.
The artillery assigned to a field army should be of such mobility,
power, variety and number as to insure the success of its purpose and
to enable this success to be gained with the minimum of casualties.
The latter point must receive careful consideration in studies of
organization, for without adequate artillery preparation and support
the successes of the most gallant infantry can in a series of actions
become little more than pyrrhic victories. Many actions of our
divisions in France resulted in casualties whose numbers decreased in
proportion to the number of guns with which divisions were supported.
The proportion of guns to the thousand gross strength of infantry,
cavalry, and machine guns adopted by the armies of the first class
powers before the opening of the present European War in 1914 was:
British, 6.8; French, 4.6; German, 6.4; American 3.2 (Greble Board).
During the war this proportion was constantly increased until at the
close under conditions of position or entrenched warfare it was between
8 and 12 per thousand; this varied of course with the activity in
different sectors. In quiet sectors and under conditions of maneuver,
or open warfare, which necessitated leaving much artillery behind, it
was about 6 per thousand.
A program of types of artillery weapons should be founded on the object
and the means—that is, the destruction of the target and the projectile
to accomplish this. In the study of an artillery program there are two
methods of approaching the subject. First, by starting with a minimum
weight of projectile and working up to a reasonable maximum, according
to some law and taking the corresponding calibers, a theoretical series
of guns and howitzers can be expressed. For instance, if the law be
doubling the weight of the projectile the series of types could be:
Projectile of 13 pounds, caliber 3”.
Projectile of 26 pounds, caliber 4”.
Projectile of 52 pounds, caliber 5”.
Projectile of 104 pounds, caliber 6”.
Projectile of 208 pounds, caliber 8”.
Projectile of 416 pounds, caliber 10”.
Projectile of 832 pounds, caliber 12”.
Projectile of 1664 pounds, caliber 14”.
The second and more logical method, and one followed in our service,
is to consider the artillery missions and determine the types best
suited irrespective of any theoretical series of weights and calibers.
However, in the discussion of artillery missions and the proper types
for their fulfillment there is a remarkable degree of unanimity of
thought on these subjects; and the above table actually contains, with
slight variations, the types that are most strongly recommended. While
granting the great variety of artillery missions that often shade into
each other, it is believed that they can best be considered in three
great classes that follow the tactical composition of a field army:
those of division, corps and army artillery.
DIVISION ARTILLERY.
=Missions.= The division artillery, first of all, must have the
mobility that will permit it to accompany the infantry of a division
and the maximum power consistent with that mobility; its object must
be primarily the infantry of the opposing division. It is therefore
bound to its own infantry with the closest bonds and its tactical use
cannot be separated from that of the infantry. The division artillery
must fire, accurately, a man killing projectile and be prepared for
quick changes of targets; it must have a great range because of depth,
both of its own and the enemy division; it must continually harass
the enemy, prevent his movement and force him into cover or protected
trenches. On the defensive it must break up the opposing infantry
formations by preparing a counter-offensive fire and by annihilating
fire on points from which the enemy attacks emerge; and, failing in
these, be prepared to use the barrage and shrapnel fire at close range.
In the offensive the division artillery must play its part in the
complex schemes of artillery preparation by cutting wire, destroying
machine gun nests, gassing areas, concentrating on infantry positions
and taking the principal part in the deep barrage that should precede
the infantry attack. Its fire, accompanying the infantry movement,
requires its own movement and by its mobility it often becomes for some
time the sole artillery protection in the preparation and holding of a
position which has been taken.
=Light Gun and Howitzer.= The consensus of opinion of artillery
officers is that the division artillery missions are best fulfilled by
a light field gun and a light field howitzer having a range of at least
11,000 yards. While differing in mechanical features, the field guns
of the different European countries are practically of the same type
and, though constant effort is being made to improve details, they can
be stated as generally satisfactory to their own governments and not
liable to any radical changes. The general type of field gun, while
capable of fulfilling most of the division artillery missions, must be
supplemented by a proper howitzer. There are many instances where the
terrain or the lay of the land offers such protection to the infantry
that the field gun cannot bring an effective fire. The howitzer has
the great advantage that with the proper set of propelling charges
and, therefore, choice of trajectories for the same range, protected
positions can be chosen for howitzers that guns could not use, and
angles of fall obtained on objectives that the normal ammunition of
guns would not give. The low muzzle velocity of howitzers admits of
their almost continuous use in harassing fire and allows the use of a
projectile double the weight of that of a field gun. Such a howitzer
renders excellent service in wire cutting and is a useful projector of
gas shells. To insure the mobility required of all divisional artillery
the weight of the howitzer and carriage should not exceed that of the
field gun, or about 4,500 pounds.
=Light Gun Discussion.= The consensus of opinion of all artillery
officers—French, English and American—is that the 75-mm gun, or
approximately this caliber, firing a 15-pound projectile or a
projectile of approximately this weight, and having a range of not less
than 11,000 yards, is a satisfactory weapon at the present time for
use with the division artillery. The projectile in question, whether a
shrapnel or a high explosive shell, satisfies adequately the criterion
of man-killing. At the close of the war the nations were not entirely
in accord with respect to their conception of an up-to-date carriage
for a light field gun. All the nations whose tendencies have been
considered in this report have experienced to a varying degree with
field gun carriages, particularly in a desire to design a carriage
permitting a greater angle of elevation and greater movement of the gun
in the traverse. The Italians have expressed themselves in the modified
Deport Carriage; this vehicle is of the split trail type and permits
an elevation in excess of 75 degrees, and a traverse on each side of
the center of the carriage of about 20 degrees—about 356 mils. Up to
the time that the board left France it was not possible to learn the
French decision in the matter of a split trail carriage for their light
field gun. It is known, however, that several types of this carriage
have been designed and tested; it is known, also, that considerable
favor has been found with the American 1916, which type has been tested
under the auspices of the French Government. In England, however, the
board was not able to develop any enthusiasm for the split trail type,
although the matter had been seriously considered. In that country
the up-to-date field gun carriage appears to be adequately expressed
in their new 18-pounder. The vehicle upon which this gun is mounted
permits an elevation of 37 degrees and an axle traverse of 4½ degrees
on each side. The trail is a box trail and the carriage is simple and
steady in its construction and lends itself to rapid production.
=Motorization.= At some time in the future it is probable that all
the division artillery will be motorized. The result of such a change
in the prime mover would be to remove the present restriction as to
weight of gun and carriage. The board senses a demand in the near
future for a light field gun having a maximum range of approximately
15,000 yards; such a range may be achieved by increasing the muzzle
velocity and, perhaps, the weight of the projectile, although change
in the form of projectiles will give some improvement over the present
ranges. It is probable that the limiting features in the design of
field guns of the future will be the requirement that it should pass
safely over temporary pontoon bridges and that the weight and form and
size of ammunition must be such that the present rate of fire will
not be slowed down. The board is of the opinion that, except as to
perfection of details, the limit of carriage design, as expressed by
the most modern type of box-trail and split-trail carriages, has been
reached; and feels that with the advent of motor transportation the
tendency will be toward a gun mounted on a self propelling carriage and
expressing the desires of the field artillery with respect to maximum
horizontal and vertical arcs of fire.
=Light Gun. Ideal.= A gun of about 3” caliber on a carriage permitting
a vertical arc of fire of from 5 degrees depression to 80 degrees
elevation and a horizontal arc of fire of 360 degrees; a projectile
weighing not over 20 pounds, shrapnel and high explosive shell of
satisfactory man-killing characteristics with maximum range of 15,000
yards; fixed ammunition, smokeless, flashless propelling charge; time
fuse for shrapnel. With shell having safe fuses with different lengths
of delayed action after they land. The high explosive shell should
be of one type only. Two propelling charges should be furnished, a
normal charge for about 11,000 yards range and a super charge for
maximum range. The proportion should be 90% of the former and 10% of
the latter. A maximum rate of fire of 20 rounds per minute is deemed
sufficient.
=Light Gun. Practical.= For the present, arm brigades with 75-mm
materiel. Models 1916, 50%, and 1897 (French), 50%.
=Transport. Ideal.= Mechanical transport is the prime mover of the
future. The introduction of mechanical transport will undoubtedly cause
far-reaching changes in the types of gun carriages. It is not possible
now to state just how far this will go or whether a gun mounted on a
self propelled vehicle or one mounted on some type of trailing vehicle
will be the final result. Both types may be necessary. It is urgent
that study and development be carried along these lines, as we are on
the verge of changes fully as radical as the introduction of the long
recoil field gun and carriage, and the country first utilizing the new
capabilities opened up by mechanical traction and the caterpillar will
have a great advantage in the next war. A limit of 4,500 pounds behind
the team has heretofore been imposed on the artillery of this class.
The corresponding limit in the future will probably be that imposed by
pontoon bridges.
=Transport. Practical.= Therefore it is thought that four regiments
of 75-mm guns (two regiments of French Model 1897, and two regiments
of U. S. Model 1916) should be immediately equipped with motors, the
remainder to be horsed; mechanical transport to gradually replace horse
only after the tractor demonstrates its superiority in service.
=Light Howitzer Discussion.= The consensus of opinion of American
army officers consulted is that a howitzer about 4” in caliber,
firing a projectile weighing from 25 to 30 pounds at a maximum range
greater than 10,000 yards, is required. This opinion is concurred in
by the French, Italians and English, and it appears to be definitely
established that the mobility of the light field howitzer should be
practically the same as that of the light field gun. The British
army was equipped with a 4½” howitzer, firing a projectile weighing
35 pounds and with a maximum range of 7,700 yards; the weight of the
howitzer limbered is 4676 pounds—150 pounds more than the weight of the
18-pounder field gun. No evidence was found that the British Government
intended making any alterations in the design of this howitzer;
naturally they will attempt to increase the range, power and accuracy
of the projectile by change in its weight, its capacity and its form.
The French artillery was not equipped with the light field howitzer
of approximately the same weight as the 75-mm field gun. During the
war it was found impracticable to construct a lighter howitzer without
interfering with the production of other calibers which were considered
more important. In the earlier stages of the war the Italian artillery
was not equipped with a light field howitzer; however, before the
end of 1917 orders were placed for several hundred howitzers of the
105-mm type. It should be noted that several hundred howitzers of this
caliber were being constructed before the armistice and that many have
been captured from the Austrians by the Italians; this, so far as the
Italians were concerned, makes it certain that a light field howitzer
will be furnished by the Italian army. The German and Austrian armies
were equipped with a howitzer of the light field type; this weapon had
a caliber of 105-mm type.
It fired a projectile weighing 34.54 pounds at a maximum range of
10,500 yards. (Streamline shell.) The weight of the howitzer limbered
was 4,500 pounds. In the opinion of the board, the Germans have
proceeded on sound principles in their development of the light field
howitzer. Their ’98 model was a companion piece to their ’96 field gun
and in the years that passed from 1898 to 1916, which included their
early war experience, they kept to the idea of the relation of the two
pieces even to the extent of including in a field artillery regiment
one battalion of light howitzers. Their 1916 models of both light gun
and howitzers show the endeavor to keep the pieces in the same class;
that is, the weight of the gun and howitzer in action nearly the same,
2,750 pounds and 2,700 pounds; the weight of the gun limbered and the
howitzer limbered are the same, 4,500 pounds; the elevation of both the
same—minus 10 to plus 40 degrees; the carriages are of the same type;
and the extreme ranges of gun and howitzer are respectively 11,700 and
10,500 yards. From the foregoing it is seen that all the important
belligerents except the French and the Americans were equipped with
a light field howitzer firing a projectile about twice the weight of
the light field gun projectile and having otherwise the same general
characteristics. There is no evidence to show that the fire of the
French and the American artillery was not fully effective as that of
any other artillery; however the testimony of the French and American
artillery officers is to the effect:
(a) That the lightest howitzer in use, i. e., the 155-mm, was not
sufficiently mobile to be a suitable companion piece for the 75-mm gun.
(b) That many times the fire of the 75-mm gun proved ineffective due to
its flat trajectory; a howitzer would have been more effective in the
attack of certain targets.
(c) That a large volume of fire is necessary.
(d) That while the 155-mm howitzer is more powerful than the light
field howitzer its consumption of ammunition for many purposes is
wasteful and extravagant and its volume of fire is insufficient.
(e) That the light howitzer is particularly suited for the destruction
of wire entanglements; its better accuracy and more powerful projectile
make it more suitable than the field gun for that purpose.
(f) That the 75-mm field gun projectile is not so satisfactory a gas
shell as the howitzer projectile which has greater weight.
=Light Howitzer. Idea.= A weapon of about 105-mm caliber on a carriage
permitting a vertical arc of fire from minus 5 degrees to plus 65
degrees, and a horizontal arc of fire of 360 degrees. Efforts should be
made to develop a carriage which can be used interchangeably for the
division light gun referred to above and this howitzer. The projectile
should weigh about 30 to 35 pounds and should include both shell
and shrapnel. A maximum range of 12,000 yards will be satisfactory.
Semi-fixed ammunition with varying charges should be used, otherwise
the ammunition should be similar to that provided for the 75-mm guns.
=Light Howitzer. Practical.= For the present, the division should be
armed with the 155 howitzer, Schnieder, but active development and
test should be made on a type as stated under “Ideal” above, and with
the ammunition and other accessories to it. Upon the development of
the carriage as nearly approximating the ideal as may be practically
possible, efforts should be made to secure quantity production in
order that it may be incorporated in the division as recommended. In
addition, a split trail carriage for this howitzer should be developed.
=Transport.= The light howitzer should have the same means of transport
as the light field gun and the same remarks heretofore made as to the
probable future development of the field gun also apply to the howitzer
carriage.
CORPS ARTILLERY.
=Missions.= It will be noted above that the division artillery missions
did not include their own protection against the enemy artillery. This
counter-battery work is the principal mission of the corps artillery.
The corps artillery has also the mission of extensive harassing and
interdicting fire along the corps front and to a greater depth than the
capabilities of the division artillery; also of destructive fire on
strong points as well as on railroad facilities and points of supply.
For the accomplishment of these corps artillery missions there are two
types of artillery necessary, a gun and a howitzer, each having 16,000
yards range and each weighing with the carriage about 11,000 pounds.
There is another class of artillery called anti-aircraft artillery to
be considered. This is used first in providing anti-aircraft defense
for army zones, for certain areas in rear of armies or along a certain
line of anti-aircraft defense.
=Medium Gun Discussion.= The consensus of opinion of artillery
officers—Italian, English and American—is that a medium gun of about
6” caliber is necessary. The medium type gun furnished to the American
army was the 4.7 (Model 1906). This gun has a maximum elevation of 15
degrees with a corresponding maximum range of 8,750 yards. The British
army was equipped with the 5” gun—the carriage permits a maximum
elevation of 21 degrees and 30 minutes, giving a maximum range of
12,500 yards. The French army was equipped with, to a certain extent,
the 105-mm and the 140-mm gun. The 105-mm gun a maximum elevation of
37 degrees, with a maximum range of 13,900 yards. The 140-mm gun has
a maximum elevation of 30 degrees and, with a high velocity, has a
maximum range of 19,500 yards. The French 105-mm gun is a modern weapon
(1913). The German artillery was equipped with a 105-mm gun (M-1917)
with a maximum elevation of 45 degrees, and a maximum range of 16,000
yards. The German army was also equipped with the 130-mm gun, having
a maximum range of 16,500 yards. The Austrian army was similarity
equipped. The Italians were equipped with a 105-mm gun essentially of
the same characteristics as the French 105-mm M-1913.
=Medium Gun. Ideal.= A caliber of between 4.7 and 5” on a carriage
permitting a vertical arc of fire of from minus 5 degrees to plus
80 degrees; a horizontal arc of fire of 360 degrees. Shrapnel and
shell weighing not over 60 pounds, maximum range 18,000 yards; with
semi-fixed or separate loading ammunition permissible.
=Medium Gun Practical.= Corps artillery should be armed with the
present type 4.7” gun, Model 1906, except that at least one regiment
should be armed with the British type 5”-guns purchased abroad.
=Transport.= All corps guns should be developed for long, rapid hauls.
Similar ammunition vehicles should be developed. The wheels for the gun
carriage should be rubber-tired.
=Medium Howitzer.= In the opinion of the French, Italians, British
and the Americans, the 155-mm howitzer (Schnieder) was conspicuously
successful in the present war. It should, therefore, be retained
as a type. The howitzer and carriage as it stands at present, is a
highly satisfactory and efficient piece of armament. For the future
it is believed that effort should be made to increase the range by
improvements in the form of projectile, and it is believed that
the form of howitzer and carriage should be studied with a view of
obtaining, through modifications, a maximum range of approximately
16,000 yards.
Many batteries of 155-mm howitzers (Schnieder) were motorized in the
American Army in France, and the consensus of opinion is definitely
toward the retention of this form of prime mover. It is interesting to
note that all the important belligerents have settled upon a howitzer
of approximately 6” in caliber, and otherwise essentially of the same
ballistic characteristics as the type in question. The projectile of
this caliber is the smallest projectile which can be called upon to
give adequate mining effect against material targets of semi-permanent
nature. The place of this howitzer is, therefore, determined by
considerations of its destructive ability. It is a splendid destruction
and neutralizing weapon.
=Medium Howitzer. Ideal.= A caliber of about 155-mm on a carriage
permitting a vertical arc of fire of from minus 5 degrees to plus 65
degrees; and a horizontal arc of fire of 360 degrees. The projectile
should not weigh over 100 pounds and should be interchangeable with
projectiles for other guns of this caliber referred to later on. High
explosive shell, only, should be supplied.
=Medium Howitzer. Practical.= The corps should be armed with the 155-mm
(Schnieder) howitzer referred to above. The type of fuses for shell
should be super quick and long delay.
ARMY ARTILLERY.
=Missions.= In addition to the division and corps artillery fulfilling
the missions outlined above there must be additional artillery
available. There are missions of interdiction, neutralization and
destruction which fall beyond the activities or capabilities of
the normal corps or medium field types; there must exist a surplus
of division or corps types, properly transported, for strategic
reinforcements of divisions and corps during such times as the normal
allotment to such units is insufficient; there must be artillery
of special purpose—mountain artillery, trench and super guns and
howitzers. Of the above additional artillery, a type of heavy field gun
and a type of heavy field howitzer are considered normally necessary
in the armament of a field army; the gun should have a range of
approximately 25,000 yards, and the howitzer a range of about 18,000
yards. These weapons are more powerful than the medium field types, add
range to the interdiction and harassing and to the neutralization and
destruction possible with the corps type. Considering the paragraphs
pertaining to divisional artillery and the introduction to corps
artillery _it will be seen that the normal artillery of a field army
can be accomplished by the assignments of two caliber, i. e., two light
weapons, two medium weapons and two heavy weapons—a gun and a howitzer
in each class—and a satisfactory anti-aircraft gun_.
=Heavy Field Gun.= The consensus of opinion of all artillery
officers—British, Italian and American—is that the heavy field gun
should be of approximately 6” caliber and that guns of greater caliber
than this are necessary in limited number for field operations. The
French were constructing 194-mm guns during the latter stages of the
war. It is believed that in developing this type of gun the French
were actuated almost entirely by the necessity for increased range,
since the German 150-mm gun, Model 1916, outranged the G. P. F. by
approximately 5,500 yards. The French have recently made considerable
progress in securing the necessary increase in range with the G. P. F.
All of the principal nations engaged in the war used a heavy field
gun of approximately 6” caliber. This type has given such general
satisfaction that its continuance is assured. The principal mission of
the heavy field gun is harassing and interdiction fire, and for these
uses the 6” projectile is sufficiently heavy. The maximum practicable
traverse and elevation should be provided by the carriage of the heavy
field gun. The G. P. F. carriage has given general satisfaction, but
its wide tread and the excessive time required to occupy a position
are very objectionable features. It is the consensus of all artillery
officers—French, British and American—that the heavy field gun should
be of approximately 6” caliber and with a range in excess of 25,000
yards, with not less than 60 degree traverse, weighing not more than 12
tons, limbered, capable of occupying and leaving a position quickly,
and with a width of tread which does not prevent two-way traffic on
ordinary roads. The Italians differ from this opinion only in that they
are satisfied with a maximum range of 18,000 yards.
=Heavy Field Gun. Ideal.= A caliber of about 155-mm on a carriage
permitting a vertical arc of fire from 0 degrees to plus 65 degrees;
with a horizontal arc of fire of 360 degrees. The maximum range should
be about 25,000 yards.
=Heavy Field Gun. Practical.= Arm with the present type 155-mm G. P. F.
and carry on experiments for type of carriage as outlined for division
field gun. The fuses should be super-quick and short delay.
=Transport.= All artillery of this type should be motorized and tested
and experiments for ammunition vehicles to correspond with the types of
carriages developed, and should be carried on simultaneously.
=Heavy Field Howitzer.= No type of heavy field howitzer developed
during the war has given general satisfaction. The consensus of all
army artillery officers—French, English and American—is that two
calibers of howitzers are necessary—one a companion piece for the 6”
gun and one of the maximum possible power consistent with the necessary
mobility. The lighter of these two howitzers should have the same
mobility as the 6” gun, with a caliber of about 8” and a maximum range
of not less than 16,000 yards. The heavy field howitzer should be of
about 9.5” caliber with a range in excess of 16,000 yards; the carriage
should provide for wide traverse and must have sufficient mobility
to accompany the army in the field. It will probably be necessary to
transport this howitzer in more than one load, and the maximum weight
of any load should not exceed 12 tons. The average time necessary for
occupying a position should not exceed six hours under actual field
conditions.
=Heavy Field Howitzer. Ideal.= A caliber of about 8” on a carriage
permitting a vertical arc of fire of from 0 to plus 65 degrees; and
a horizontal arc of fire of 360 degrees. The maximum range should be
18,000 yards.
=Heavy Field Howitzer. Practical.= Use at present 8” material of
British design which is on hand.
=Railway Artillery.= The war has demonstrated the necessity for long
range and powerful guns for distant interdiction and harassing work
and for super-heavy howitzers for the destruction of semi-permanent
fortifications. Artillery of these types can best be mounted on railway
carriages and this type of mount offers no serious disadvantages since
these guns will not be used except with large forces which require
extensive railroad systems for their supply. This does not apply to
guns of the type used to bombard Paris; such guns have no military
value and their construction is not justifiable.
ANTI-AIRCRAFT GUNS.
=Light Gun. Ideal.= Caliber about 3” with initial velocity of at
least 2,600 f. s.; semi-automatic breechblock, mounted on carriage,
permitting 80 degrees elevation and 360 degrees traverse; projectiles
weighing not less than 15 pounds, of one type high explosive shell with
maximum ballistic qualities and as large explosive charge as possible;
fixed ammunition; smokeless, flashless powder, mechanical fuse. In
this type every effort must be made to increase the rate of fire and
decrease time of flight; this latter is limited only by considerations
of a reasonable accuracy life for the gun.
=Light Gun. Practical.= Arm units with present 3” anti-aircraft
equipment. Continue experiments leading to the development of the ideal.
=Transport. Ideal.= Caterpillar mount or caterpillar trailer mount
drawn by caterpillar tractor, each unit to permit a sustained speed of
12 miles per hour.