He makes large deflection shifts by shifting the bipod assembly and keeps the bubbles level during firing. High explosive is used for both fragmentation and blast effect against personnel and light-skinned vehicles. There must not be a visible gap between the fuze and cartridge body. (1) The M772A1 fuze is a MTSQ. The cartridge must not be fired below charge 3. A spring-loaded locating catch is behind the elevating gear housing, which locates the plain leg in its supporting position for level ground. PDF Introduction to Crew Served Weapons B3m4078 Student Handout (2) The M524-series fuze has two function settings: superquick/impact (SQ/IMP) and delay. . c. Upon receiving the command REFER, REALIGN AIMING POST, two actions take place at the same time in the mortar squad. The sight bracket is attached to the buffer carrier, which is fitted to the traversing screw assembly. This round may be stored in a horizontal position. The round is still safe to handle and transport if the safety wire is reinserted. CANNON . News. With standard mortar, the maximum effective range is close to 4,000 metres; with a long-range system, this increases to nearly 4,500 metres. Examples are: 60mm, 81mm, and 120mm Mortar Increments with Ball Powder Propellants The M252 81mm Medium Extended Range Mortar is a crew-served, medium weight mortar which is highly accurate and provides for a greater range (4,500 meters to 5,650 meters) and lethality than the . If not, he may still fire at the desired range by selecting a charge zone having a higher elevation. PDF Tabular Firing Tables - United States Army b. M252 81mm Medium Extended Range Mortar - Federation of American Scientists It engages the 1 3/4-inch flats on the setting ring or the fuze head. Propelling charges are covered or protected from dampness or heat. This cartridge is ballistically matched to the M374A2, M374A1, and M375 HE cartridges, and weighs about 9.12 pounds. The muzzle end has a short tapered lead-in which acts as a . (7) When opening an ammunition box, the ammunition bearer ensures the box is horizontal to the ground, not nose- or fin-end up. It is fitted with a standard pull wire and safety pin that are removed immediately before firing. The squad leader points to the exact spot where the mortar is to be mounted. 9301 Chapek Road., Bldg.1458 Table 4-2. The squad leader stands behind the mortar where he can command and control his squad. Baseplate placed against baseplate stake. Complete cartridges are always handled with care. The cartridge uses the M218 propelling charge, which consists of four horseshoe-shaped increments fitted around the tail. c. The assistant gunner lifts the bipod and stands it on its elevating leg so that the elevating handwheel is to the rear and the plain leg is to the front. It has two types: type 1 resembles the M734 fuze, and type 2 resembles the M935 fuze. The components of the mortar consist of a canon, sight, mount, and baseplate. b. One-quarter turn on the adjusting nut equals one turn of the traversing handwheel. The types of fuzes described in this paragraph are point detonating, proximity, mechanical time, multioption, and dummy. The M1 became the standard American . Attached to the arm is the cross-leveling mechanism, which is attached to the clamp assembly at its upper end. Figure 4-7. With the mortar mounted and the sight installed, the gunner lays the sight on the two aiming posts (placed out 50 and 100 meters from the mortar) on a referred deflection of 2800 mils and an elevation of 1100 mils. FM 23-90 Chptr 4 81-mm Mortar, M252 - GlobalSecurity.org The ammunition that can be fired by the 81-mm mortar, M252, is identified and described herein. 50mm? 60mm? 80mm? A guide on picking the right mortar for you If the mortar section is to operate quickly and effectively in accomplishing its mission, mortar squad members must be proficient in individually assigned duties. In addition to loading, he swabs the bore after 10 rounds have been fired or after each fire mission. When cartridges have been prepared for firing, but are not used, all powder increments and safety wires are replaced. The fuze body is graduated from 0 to 25 seconds in 1-second intervals; 5-second intervals are indicated by bosses. Joint Tables of Allowance; PB - Professional Bulletins; STP - Soldier Training Publications; TC - Training Circulars; . Ammunition Lot Number. The mortar is within two turns of center of traverse. System (including basic issue items) mortar, 81-mm: m29a1 and m29; firing cartridge, he, m374a2 and m374; cartridge, wp, m375a2 and m375 (s&i by prop see details, footnotes) ardec: ft 81-al-4(abr) active: 12/24/1970: firing tables for mortar, 81mm, m29 and m1 firing cartridge, illuminating, m301a3 with fuze, time, m84a1, height of burst, 600 meters (s&i by prop see details . No tools are needed to set the fuze, and the setting can be changed several times without damaging the fuze. The 0-second boss is wider and differs in shape from the other body bosses; the safe setting position is indicated by the letter "S" on the fuze body. PDF Principles of Fire Support B2c2437 Student Handout Correct way to open an ammunition box. The term "indirect fire" means firing at an enemy without having a. This may preclude moving the bipod. The cartridge is painted light green with black markings and one narrow brown band. .50: BALL, M2 (S&I BY PROP SEE DETAILS, FOOTNOTES), FIRING TABLES FOR WEAPON, 5.56MM, M16A1 WEAPON, 5.56MM, M16A2 WEAPON, 5.56MM, M249 AND WEAPON, 5.56MM, M4 FIRING CARTRIDGE, BALL, M855 CARTRIDGE, TRACER, M858 CARTRIDGE, BALL, M193 CARTRIDGE, TRACER, M196 (S&I BY PROP SEE DETAILS, FOOTNOTES), MACHINE GUN, 7.62-MM: M60 ON MOUNT, MACHINE GUN: 7.62-MM, M122 AND MACHINE GUN, 7.62-MM: M73 ON TANK, COMBAT, FULL-TRACKED: 105-MM GUN, M60 SERIES AND RIFLE, 7.62-MM: M14; FIRING CARTRIDGE, 7.62-MM, BALL, NATO, M59; CARTRIDGE, 7.62-MM, BALL, NATO, M80; CARTRIDGE, 7.62-MM: AP, NATO, M61 AND CARTRIDGE, 7.62-MM: TRACER, NATO, M62 (REPRINTED W/BASIC INCL C1) (S&I BY PROP SEE DETAILS, FOOTNOTES), ADDENDUM TO FT 8-Q-1 FOR PROJECTILE, HE, M404 (S&I BY PROP SEE DETAILS, FOOTNOTES), ADDENDUM TO FT 8-J-4 FOR PROJECTILE, HE, M404 (S&I BY PROP SEE DETAILS, FOOTNOTES), ADDENDUM TO FT 8-T-1 FOR PROJECTILE, HE: M509A1 (S&I BY PROP SEE DETAILS, FOOTNOTES), CANNON, 8-INCH HOWITZER, M201A1 ON HOWITZER, HEAVY, SELF-PROPELLED, 8-INCH, M110A2 FOR LOW ANGLE FIRING PROJECTILE, HE, M509A1 USING REGISTRATION DATA FOR PROJECTILE, HE, M106 (S&I BY PROP SEE DETAILS, FOOTNOTES), CANNON, 8-INCH HOWITZER: M2 AND M2A1 ON HOWITZER, HEAVY, TOWED: 8-INCH, M115; CANNON, 8-INCH HOWITZER: M47 ON HOWITZER, HEAVY, SELF-PROPELLED, FULL TRACKED: 8-INCH, M55; CANNON, 8-INCH HOWITZER: M2A1E1 ON HOWITZER, HEAVY, SELF-PROPELLED: 8-INCH, M110; FIRING PROJECTILE, HE: M106 AND PROJECTILE, CHEMICAL: M426 (S&I BY PROP SEE DETAILS, FOOTNOTES), CANNON, 8-INCH HOWITZER, M201 ON HOWITZER, HEAVY, SELF-PROPELLED: 8-INCH, M110A1 AND CANNON, 8-INCH HOWITZER, M201A1 ON HOWITZER, HEAVY, SELF-PROPELLED: 8-INCH, M110A2 AND FIRING PROJECTILE, HE, M106 PROJECTILE, CHEMICAL, M426 (S&I BY PROP SEE DETAILS, FOOTNOTES), CANNON, 8-INCH HOWITZER: M201A1 ON HOWITZER, HEAVY, SELF-PROPELLED, 8-INCH, M110A2; FIRING PROJECTILE, HE, RA; M650 AND PROJECTILE, ATOMIC: M753 AND M753A1 (S&I BY PROP SEE DETAILS, FOOTNOTES), CANNON, 8-INCH HOWITZER, M201A1 ON HOWITZER, HEAVY, SELF-PROPELLED: 8-INCH, M110A2 FIRING PROJECTILE, HE, M509A1 (S&I BY PROP SEE DETAILS, FOOTNOTES), CANNON, 14.5-MM GUN, M31; ARTILLERY TRAINER FIRING FUZED CARTRIDGES, M181, M182 AND M183 (S&I BY PROP SEE DETAILS, FOOTNOTES), GUN, 20-MM, AUTOMATIC, M139; FIRING CARTRIDGE, 20-MM, HEIT, M599; CARTRIDGE, 20-MM, TPT, M206 AND CARTRIDGE, 20-MM, APIT, M601 (S&I BY PROP SEE DETAILS, FOOTNOTES), FIRING TABLES FOR CANNON, 25MM GUN, M242 ON INFANTRY FIGHTING VEHICLE, M3 FIRING CARTRIDGE, APDS-T, M791 CARTRIDGE, HEI-T, M792 CARTRIDGE, TP-T, M793 CARTRIDGE, TPDS-T, M910 (S&I BY PROP SEE DETAILS, FOOTNOTES), GUN, AUTOMATIC, 40-MM, M1 AND GUN, DUAL AUTOMATIC, 40-MM, M2; FIRING CARTRIDGE, HE-T, SD, MK 2 WITH FUZES, PD, MK 27, M64A1, M71 OR NO. REFERRING OF THE SIGHT AND REALIGNMENT OF AIMING POSTS USING M64 SIGHT. The equipment is placed out the same as for the gunner's examination (Chapter 9). An ammunition lot number is assigned to each ammunition lot, which is marked on each cartridge and packing container. See Chapter 3, paragraph 3-14 for a detailed discussion of malfunctions. The components of the mortar consist of a cannon, mount, and baseplate. He performs other duties as the squad leader directs. (4) The blast attentuator device is secured correctly. The fuze arms and functions normally when fired at any angle of elevation between 0800 and 1406 mils at charges 1 through 9. The propelling charges are assembled around the fin assembly shaft. (1) The barrel is clean and free from grease and oil both inside and out. Proximity-fuzed short cartridges, which are duds, contain a complete explosive train and impact element. The propellant increments are ignited, which produce rapidly expanding gases that force the cartridge from the barrel. The terms cannon and barrel are used interchangeably in this chapter. The assistant gunner places his right hand palm up (1 inch from the muzzle end) under the BAD and his left hand palm down (1 inch from the muzzle end) on top. Training practice is used only for training. How the RCGM works: Target coordinates are programed into the RCGM using a portable GPS setter. The gunner levels the elevation bubble by turning the elevation micrometer knob and reading the setting on the elevation scale and elevation micrometer--this setting is the minimum mask clearance. The aluminum tail assembly has six integral fins equally spaced around the rear, which stabilize the round in flight. At the muzzle end is a cone-shaped blast attenuator device (BAD) that is fitted to reduce noise. (c) The gunner determines mask and overhead clearance by sighting along the barrel with his eye near the breech plug. (4) The bipod locking latch is locked, securing the barrel clamps. All mortar cartridges are painted to prevent rust and to identify their type. Rheinmetall Defence - mortar systems He exposes 1 inch (25 millimeters) of cross-level shaft and folds the handle. c. The M375A2, M375A1, and M375 cartridges may also be used. After the bands are broken and the box opened, the rounds should be removed by allowing them to roll out along the lid of the box (Figure 4-8). f. Ammunition should be stored under cover. When the gunner is satisfied with his sight picture he announces, "Up.". FT 81-AI-3 Firing Tables Mortar, 81mm: M28A1 and M29 Mortar 81mm Self propelled M125A1 and M125 Carrier, 81mm Mortar Tracked XM755 [US Army.] CANNON, 155MM HOWITZER, M185 ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A1 HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A1B HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A2 HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A3 HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A3B HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A4 AND CANNON, 155MM HOWITZER, M284 ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A5, M109A6 AND M109A7 AND CANNON, 155MM HOWITZER, M284A2 CHROME ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A6 AND M109A7 AND CANNON, 155MM HOWITZER, M199 ON HOWITZER, MEDIUM, TOWED, 155MM, M198 AND CANNON, 155MM HOWITZER, M776 ON HOWITZER, MEDIUM, TOWED, 155MM, M777, M777A1 AND M777A2 AND CANNON, 155MM HOWITZER, M776 CHROME ON HOWITZER, MEDIUM, TOWED, 155MM, M777A2 FIRING PROJECTILE, HE, M795 PROJECTILE, HE, M795 IM PROJECTILE, HE, M1122 PROJECTILE, IR ILLUMINATING, M1123 PROJECTILE, ILLUMINATING, M1124 INCLUDES FIRING TABLES FOR PROPELLANTS: M119A2 (CHARGE 7R), M203A1 (CHARGE 8S), AND MODULAR ARTILLERY CHARGE SYSTEM (MACS) PROPELLANTS: M231 (CHARGES 1L AND 2L), M232 AND M232A1 (CHARGES 3H, 4H AND 5H) (S&I BY PROP SEE DETAILS, FOOTNOTES) . He opens the cross-level handwheel, traversing handwheel, and barrel clamp. HE ammunition is used against personnel and materiel. The table on the right describes the three most common setups. It is especially useful if the baseplate sinks deep into the ground during prolonged firing. As soon as the sight data are announced, the gunner places it on the sight. e. The second ammunition bearer stands to the right rear of the mortar behind the ammunition bearer.