Release Firing Device M1 (Obsolete)

General: The release-firing device M1 is a mechanical device designed for firing ex-plosive charges by means of the removal of a restraining load from the device. A restrai-ning load of at least two pounds is required. When the load is removed, a spring lever strikes a fring pin, which detonates a percussion cap. This, in turn, set off a non-electric cap crimped to the base. This cap detonates the explosive charge. There is a safety pin, and a lever interceptor which serves as a positive safety pin.

Description: The principal parts are the body, a square metal container with a pro-truding nub threaded to receive the standard firing nipple; the latch; the spring lever; and the firing pin. The latch, when held down against the body by the safety pin or pres-sure on the box, engages the spring lever and prevents it from firing. The firing pin is held rather loosely in place, having leeway for slight horizonatl motion. When the nipple is threaded on, it forces the firing pin back as far as it can go, the firing pin point resting squarly against the surface of the percussion cap.

Operation: When the device is set with a weight on top and both safety pins remo-ved, it is an armed condition. If the restraining weight is removed, the latch release the spring lever. The spring lever will then snap down against the firing pin and drive it into the percussion cap in the standard nipple base, setting off the charge.

Figure 248. Release Firing Device M1