4-inches long spotwelded to the base of the
body serves as a nailing bracket. Four release-
type firing devices are packed per chipboard
box, twenty boxes (80 devices) per wooden box,
weight, 44.1 pounds.
knurled knob and a pawl, and is attached to the
outer end of the release pin.
(c) A positive safety pin, one leg of
which passes through a hole in the body
between the firing pin and the primer, prevents
the firing pin from striking the prinmer should
the firing pin be accidentally released.
other leg of the safety pin is bent around the
body to keep it in placeduring shipment and
handling. An anchor cord (12-inches long),
attached to the eyelet on the body, is used to
anchor the firing device firmly during installa-
tion. Five pull release type demolition firing
devices M3 with two 80-foot spools of trip wire
are packed per package, 5 packages per inner
package, 6 inner packages (150 devices and 60
spools) per wooden box, weight 49.9 pounds.
(6) Firing device, demolition: M1, release-
type (figs. 1-30
and 1-31). Release-type demoli-
tion firing device M1 is designed to be actuated
when a restraining weight is removed from it
and is intended for use in setting up booby-
traps. The restraining weight is applied at the
The tiring device is
time of installation.
restrained from firing as long as there is a load
greater than 3 pounds on the top face of the
latch. The firing mechanism of this device is
Figure 1-27. Pull-type demolition firing device M1-cross section
approximately 2-inches square by 3-inches long.
It is fitted with a cover at one end and a
(7) Firing device demolition: Multipurpose
threaded hole to receive a rimed coupling base
at the opposite end. The body houses a spring
(a) The M142 is a mechanical firing device
lever, a spring, and a firing pin. One end of a
intended for use with anti-personnel mines and
steel latch engages a lip on the lever, the remain-
demolition charges when setting up boobytraps.
ing portion of the latch rests on top of the
The basic component of the device is a mechani-
device and, as issued, is held in place by a safety
cal switch designed for actuation (to initiate the
pin. This arrangement holds the lever in the
explosive) by pressure, pull, pressure release or
set position. Two 3/16-inch holes are provided
tension release. In addition to its four mode
in the sides of the body, to permit the insertion
capability, the M142 can be used to ignite either
of a nail or heavy gage wire to act as an addi-
a blasting cap (as other firing devices) or a time
tional safety device by intercepting the lever
blasting fuse for setting a short delay type
and preventing it from striking the firing pin
boobytrap. The device is weather sealed and
should remature functioning occur during
will function under water.
installation A strip of metal 3/4-inch wide and