July-August - Air Defense Artillery School

COAST ARTILLERY
COLONEL DONALD I-I. S:'UTH
LIEUTENANT COLONEL 'V.~1. VESTAL
LIEUTENANT COLONEL ANDREW \V. CLHIENT
LIEUTENANT COLONEL \VILLIS A. PERRY
BOARD NOTES
AI/) il/ail'idlwl, wllether or 'lOt lIe is (I melllber of the sen'ice, is illvited to submit cOllstmctive suggestiolls relatillg to
problems ullder stud)' by tile Coast Artiller)' Board, or to presellt m/)' new problelll tlzat properly 11I11)' be collsidered
17)'the Board. COlllmllllications sllOuld be addressed to tile Presidel/t, Coast Artillery Board, Fort Mal/roe, Virgillia.
THE COAST ARTILLERY BOARD
COLONEL \VILLlA:'1 S. BOWEN. CA.C. Presidellt
Eight-illc11 Cizalllber Spo/Ige. The Commanding General,
Army Ground Forces, has approved the recommendation
of the Coast Artillery Board that the Chamber Swabbing
Sponge T lObe adopted as standard accessory equipment
for use with the S-inch Gun Mk VI, 1\1od. 3A2, on
Barbette Carriage 1\11 and Railway Mount MIA I.
The Chamber Swabbing Sponge TIO is built of four
brush sections, the distance of the section from the center
line of the sponge and staff being regulated by leaf springs;
consequently, the diameter of the sponge head will always
confom! to that of the powder chamber. The sponge can
be easily handled by one man, and is superior in all respects
to the old type sponge.
IHodi~cl1ticm of 12-il/c1/ SllOt Tmcks. Information has
been received to the effect that a number of 12-inch batteries
with Barbette Carriages M 1917 have modified their
shot trucks to provide a powder tray on the left side. This
modification eliminates the separate powder tray and the
six men required to handle it, reduces the time required
to service the piece between rounds, and minimizes confusion
and interference at the gun and in the magazines
and corridors.
Although the provision for power ramming for batteries
of this type, ultimately to be made, will necessitate the provision
of a new shot truck, in the interim it may be practicable
for other batteries to modifv the shot trucks now in
use to provide a powder tray. /
Spraying of Powder Clwmber ill lieu of Sponging. A
report has been received by the Coast Artillery School that
a seacoast battery is spraying the powder chamber after each
shot with a fine water spray from a hose in lieu of sponging
the chamber. Since some guns are so designed that considerable
water will remain in the chamber if this method
be used, possibly resulting in a misfire, hangfire or serious
Bareback; since also the possibility of damage in battle to
the equipment necessary for continuous supply of water
under pressure would necessitate immediate availability of
a sponge as standby equipment; and in the interest of uniformity
of method, it appears undesirable that any battery
should use a water spray as an alternate method of sponging
of the powder chamber after each shot.
Combillation Sponge Rm1l11ler for 155mm Guns. The
Ordnance Department has been authorized to design and
i\I.\JOR AUSTIN E. FRIBANCE
i\IAJOR JOHN P. TRAYLOR, a.D.
CAPTAIN ROSCOE E. HARRIS, S.C.
CAPTAIN FRANCIS S. BUFFINGTON
manufacture for test, pilot models of a combination sponge
rammer for the 155mm Gun 1\11917 similar in type to that
used by the British. This combination sponge rammer consists
of a rammer head, behind which is a sponge in two
sections with a circular brush, of diameter larger than the i
chamber, in rear of them. The sponging solution is carried
into the chamber by the sponges and distributed over its
surface by the circular brush. I
Covers' for the 9011I11I Fixed GUll MOHllt 1'\113(T3). The
following accessories are to be furnished by the Ordnance
Department for use with the fixed 90mm Gun Mount 1\13: I
Breech cover (
Telescope and mount cover
1\1uzzle Cover, M324.
A gun port cover is being developed to aid further in
keeping drifting sand and snow out of the moving mechanisms.
~
Dispersioll with the lIew 8-illch GUllS. The new S-inch I
gun fires the 26o-pound target practice projectile with I
either the normal charge or the supercharge. The supercharge
should always be used in battle as the normal charge
was designed for use in practice firings to reduce 'erosion of
the bore.
Practice firings conducted in 1942 indicated that the
probable errors being developed in the field, with the nor- I
mal charge for the S-inch gun, were much larger than
expected and in general were a great deal larger than the
p.roving ground firing indicated should be expected. A special
firing of eighty rounds of the practice projectile wa~
conducted by the Board and all available reports of calibration
firings and target practices were studied and analyzed
As a result of the test and studies it was concluded that I
neither the design of the projectile and rotating band. ~h{
system of gravity ramming, nor the design of the 10a~101
tray was the primary cause of the large dispersion obtaIl1ed1
when using the normal charge. It is is believed that tht
round-to-round variations in the developed powder pres
sures, combined with the low density of loading, are thi
principal causes of the large deviations ...
~he Board r~commended that all calibration and practlct
firings with the new 8-inch gun be conducted with lht
supercharge. The Chief of Ordnance is investigating l!lt