TM 9-1375-213-12
pin is pulled, the steel safety ball restraint on the
8. When personnel are clear of danger
firing pin is removed. Hence, the only restraint
zone, fire initiating charge.
to firing pin is that afforded by firing pin release
c. Disarming. If it is
necessary, before firing,
spring. Test the concussion detonator to make
to disarm percussion detonator, follow instruc-
sure that firing pin release spring restrains fir-
tions below:
ing pin when safety cotter pin is withdrawn
(1) Insert a stick into pellet sleeve and
and spacer is released. Perform test as follows:
push spacer against safety ball.
(2) While holding spacer down, reinstall
WARNING
safety cotter pin. If cotter pin cannot be rein-
Do not look into the opening while re-
stalled, release pressure on stick and tilt deton-
moving the safety pin as the firing pin
ator so that diaphragm is facing downward.
may jump out.
Again push on spacer with stick and reinstall
1. Remove base plug.
safety cotter pin.
2. Insert a blunt instrument into the
(3) Untie and unscrew percussion detona-
opening and apply slight pressure on the firing
tor from charge.
pin. Remove the safety pin. The firing pin should
(4) Unscrew coupling base and blasting
creep forward about 1/16 of an inch.
cap assembly from detonator.
3. If firing pin falls or jumps out of
(5) Reinstall base plug.
barrel, concussion detonator is unserviceable.
(6) Reinstall sleeve plug and sleeve cover on
(b) Assembly.
pellet sleeve.
1. If firing pin release spring passes
(7) Repack in original packing.
test ((a) above), push spacer against safety
steel ball, forcing firing pin to its original posi-
2-22. Firing
Device Coupling Base
tion. Replace safety cotter pin in its original
(para 1-18)
position through pellet sleeve and spacer.
2. Remove base plug (shipping plug).
WARNING
Carefully screw in coupling base and blasting
Do not attempt to remove an unfired pri-
cap assembly with its associated gasket firmly
mer from a coupling base.
into firing mechanism.
A coupling base may be used for firing several
3. Screw device with attached coupling
primers before replacement is necessary. The
base and blasting cap assembly into threaded
originally installed percussion primer M27 is re-
cap well of demolition charge of mine. An alter-
placed by percussion primer M2 or improved No.
native method is to connect blasting cap to
3.
charge with appropriate length of detonating
cord.
2-23. Delay-Type Demolition Firing
Device M1
4. Wire or tie detonator to demolition
charge and make sure that diaphragm is free of
a. Safety Precaution.
obstructions and is clearly exposed.
(1) When screwing this device into an ex-
5. Emplace demolition charge with dia-
plosive item, it should be held with thumb and
phragm of concussion detonator facing initiat-
fingers gripping coupling that joins the two
ing charge.
halves (copper and brass) of tube.
6. Remove pellet sleeve cover. With-
(2) Time delay starts when the ampoule is
draw safety cotter pin, thus arming concussion
crushed-not when the colored identification
detonator.
and
7. Evacuate area immediately.
Change 1
2-32.1