Tension and Release Firing
Device M3 |
General: This
device is specially designed to be used with a trip wire. Unlike the
standard pull firing device, the Firing Device M3 must have the trip wire
tightly stretched, so as to exert considerable tension on the retaining rod.
The device can be activated by tripping, or by cutting the trip wire. |
Description: The parts are the body; ratchet reel, retaining rod,
striker spring, stri-ker, two safety pins, and standard nipple base. The
striker has a split base, froming four jaws which engage the nib on the end
of the retaining rod. The ratchet provides a con-venient method for
tightening and creating teh desired tension on the trip wire. Safety pin No.
1 cannot be removed until tension has been created on the trip wire to
with-drawn the retaining rod sufficiently for the large end of the safety
pin to clear the elon-gated safety-pin hole. |
Operation: When
the device has been properly installed with the explosive charge, the trip
wire is attached and tightened by means of the ratchet reel. After the
retaining rod has been withdrawn slightly, the safety pin can be removed.
The safety pin and safety-pin hole are so designed that it can be removed
only after the proper tension has been placed on the trip wire. The positive
safety pin is removed last, and the device is the armed. |
If a pull of
six to ten pounds is exerted on the trip wire, the retaining rod and striker
are pulled back and thereby compress the striker spring. As the split end of
the striker clears the internal shoulder in the body, the four jaws are
forced open and the nib on the retaining rod is pulled free. The jaws then
spring together again, and the stiker spring drives the striker down on the
percussion cap. |
If the trip
wire is cut, the striker and retaining rod move inward under influence of
the striker spring. As the split end of the striker clears the internal
shoulder in the body, the jaws of the striker are spread and pulled free of
the nib on the retaining rod by the stri-ker spring, which then forces the
striker down on the percussion cap. |
Remarks: The
device must be securely anchored to enable tension to be placed on the trip
wire without dislodging the device or explosive charge. |
Figure 252. Tension and
Release Device M3 |
|
|