FM 23-45 Basic Field Manual
26
F
IGURE 18.—Blank firing attachments
(1) The
cartridge stop attachment
is inserted by withdrawing the belt holding
pawl split pin about ½ inch and sliding the attachment over the cartridge stop, lining
up the small hole with the belt holding pawl split pin and replacing this pin. The
cartridge stop attachment acts as a guide for the blank cartridge and also as a
cartridge stop. Its chief use is to hold the cartridge in position in feedway so that the
extractor may engage its cannelure; it also prevents the entrance of a live round into
the feedway.
(2) The
muzzle attachment
is assembled to the gun by removing the front barrel
bearing, sliding the threaded end of the attachment over the barrel, and screwing it
into the barrel jacket.
b. Precautions.—
(1) Never attempt to use the muzzle attachment unless the cartridge stop
attachment is in its proper place in the feedway.
(2) Always remove the muzzle attachment before removing the cartridge stop
attachment in order to eliminate the possibility of firing ball ammunition with the
muzzle attachment still in position.
(3) See that the muzzle attachment is clean inside before using.
(4) After firing blank ammunition, clean the barrel and muzzle attachment. It is
absolutely essential that this be done before firing any other type of ammunition.
■51. S
PARE BARREL.—A spare barrel is issued for each light machine gun. In pack, this
barrel is carried on the gun and tripod hanger.
■52. A
SBESTOS MITTENS.—One pare of asbestos mittens (carried by the gunner) is
issued for use with each machine gun to facilitate the handling of the gun when hot,
particularly when moving to a new position by hand, and in changing barrels.
Section VIII
FIRE CONTROL INSTRUMENTS
■53. F
IELD GLASS, TYPE EE.—
a. Description.—
(1) The field glass, type EE (fig. 19), is an observation instrument of 6-power with
an 8
0
field of view. It contains a graduated mil scale for the measurement of small
horizontal and vertical angles. In field glasses of older manufacture there is also
provided an inverted sight leaf scale for the rapid computation of certain fire data. The
field glass complete consists of the glass and its carrying case and neck strap.
(2) The field glass proper consists of two compact prismatic telescopes pivoted
about a common hinge which permits adjustment for interpupillary distances. A scale
graduated every 2 millimeters from 56 to 74 permits the observer to set the telescopes
to suite his eye distance when the spacing of his eyes is know. The eyepiece can be
focused independently for each eye by screwing in or out. Each is provided with a
diopter scale for rapid setting when the observer knows the correction for his eye. The
zero graduations indicate the setting for normal eyes.
(3) The left telescope is fitted with a glass reticle (fig. 20) upon which are etched a
vertical mil scale, a horizontal mil scale, and on field glasses of over manufacture, a
stadia scale graduated similar to the sight leaf graduation on the service rifle, but
inverted.
b. Use.—
The field glass is used for observations and the measurement of small
horizontal and vertical angles in mils. The inverted sight leaf, when provided, is used
to pick up auxiliary aiming points in direct layering.
c. Adjustments.—
