Downloaded from https://www.everyspec.com AMCP 706210 fues of the Army were identified by a separate two major parts: "I" number which was discarded when the fuse (1) A head assembly that contains striker, was adopted for manufacture (sach as T300). firing pin, and a clockwork for delayed arming Many fizzes with "T" numbers ae still in The striker with conical striker spring is espe- existence. cially designed to permit the fuze to be fully Navy service fuses carry a "MARK" number effective when impact is at low angles. and their modifications are followed by a (2) A body that contains the arming mech- "MOD" number (such as MARK 100 MOD 1).
anism (a slider), detonator, lead, and booster There is no uniform method for designating ex- pellet. Fig. 1-7 shows the body parts of the fuze peimental Navy fuzes because each Agency in a perspective view to clarify the arming devise its own system. Howevar, many such actions. fizes carry the letter "X" as a part of their The fuze has two pull wires, connected by a nomenclature (such as EX200). Prior to World cord for easy withdrawal, that remove two set. War 1I, some Army service fuzes and projec- back pins which lock the fuze in the unarmed tiles also carried MARK numbers. Items of position to insure safety during storage, trans.
Army ammunition so marked may still be portation, and handling. The wire is removed encountered. just before inserting the projD tile into the mortar tube. Operation is as follows: 1-6 DESCRIPTION OF A REPRESENTATIVE (1) Upon firing, acceleration of the pro- IMPACT FUZE jectile produces setback forces that cause the setback pin to move to the rear (Fig. 1-7). The A typical fuze for 60 mm and 81 mm mortar safety pin is released as a result of this motion ammunition is Fuze, PD, M525, as shown in so that the spring on the safety pin pushes it out- Fig. 141. The M525 is a uuperquick, point- ward.
As long as the projectile is within the mor- detonating fuze that has been quite successful tar tube, the pin rides on the bore. Since the because of its relative simplicity'. It consists of slider is therefore still retained from moving, the BORE PIDING P!N PULL PIN GUIDE PIN FIIG I J!V~ ' . 2TRIKER BoosgrER ~~LEAD CHARGE / M44 DETONATOR CL KWR CLOCKWORK SLIDER SPRING Figure 1-6. Fuze, PD, M525 1-7