(3) Unscrew firing device from mine or
strike end of nipple sharply, indicating proper
functioning of assembly.
(c) Recock firing device by pushing firing
(4) Restore firing device to original condition
pin inward with unsharpened pencil or blunt rod
until release pin slips into place, thus expanding
slotted head of firing pin.
227. Pull-Release-Type Demolition Firing
(d) Insert positive safety pin and head
safety pin, then screw primed coupling base into
case, primer end inward. Safety pins should be
Prepare for use as follows:
free enough for easy removal after firing device
has been installed.
a. Inspect Before Use.
(2) Installation and arming.
(1) Unscrew primed coupling base from
(a) Remove primed coupling base.
firing mechanism and inspect primer.
(b) Remove protector cap from nipple and
(2) Inspect positive safety pin and safety
crimp on a nonelectric blasting cap (or screw into
pin, to see that they are in place, yet free enough
mine actuator). Screw primed coupling base into
for easy removal after firing device has been in-
(c) Screw firing device, with safety pins in
(3) Leaving positive safety pin and safety
place, into a mine or demolition charge.
pin in psition, pull winch assembly out with
finger until it is stopped by the safety pin, then
(d) Install loose tripwire, attaching anchor
release. Repeat procedure two or three times.
end first. Unspool tripwire to mine. Before con-
Winch assembly should move smoothly approxi-
necting tripwire to firing device, step off to the
mately inch and should require a force of 6 to
side and inspect for detectability of tripwire and
10 pounds. If assembly hangs or moves jerkily or
mine. If necessary, rearrange installation to ob-
too easily, examine firing device. If fault cannot
tain adequate concealment.
be corrected, use another firing device.
(e) Attach free end of wire to pull ring,
drawing up excess through pull ring so that wire
b. Installation and Arming
is taut, but without strain.
(1) Remove protector cap from nipple of
(f) Remove head safety pin, If it does not
primed coupling base and crimp on a blasting cap
pull out easily, tripwire may be too tight. Adjust
(or attach to mine activator).
tripwire if necessary. If head safety pin still
(2) Screw coupling base into device body
binds, remove coupling base and check mecha-
nism. If defective, replace faulty firing device
(3) Screw firing device (with positive safety
with a serviceable one.
pin and safety pin in place) into a mine or demoli-
(g) Using attached cord, pull out positive
safety pin slowly and carefully. If it resists a
(4) Secure tripwire at anchor end, making
gentle pull, firing pin may have been released and
certain that this tie will not slip. Unspool tripwire
is pressing against it, or leg spread of the positive
to mine or charge. Before connecting tripwire to
safety pin is excessive. If leg spread is not exces-
firing device, step off to the side and inspect for
sive but the pin still resists gentle pull, install
detectability of tripwire and mine. If necessary,
head safety pin, unscrew coupling base, and check
rearrange installation to obtain adequate conceal-
mechanism. If defective, replace faulty firing
device with a serviceable one.
(5) Attach loose end of tripwire to winch by
(h) Retain safety pins for future use in
threading it through hole in winch spindle.
Wire must be threaded through hole in
(1) Carefully insert positive safety pin first,
winch spindle, to prevent slippage and
then head safety pin into firing device. After in-
sertion, spread legs of safety pins just enough to
prevent accidental loss of pins during handling
(6) Draw up excess wire through hole in
winch spindle, Take up remaining slack by turn-
ing knurled knob until safety pin is pulled exactly
(2) Disconnect tripwire from the pull ring.