It has two types: type 1 resembles the M734 fuze, and type 2 resembles the M935 fuze. The assistant gunner carries the bipod to the front of the barrel and places the bipod feet on the ground 12 to 15 inches in front of the baseplate and astride the line of fire. The M374 cartridge is fitted with the M90 propelling charge. The ammunition that can be fired by the 81-mm mortar, M252, is identified and described herein. Range Minimum to maximum 83 to 5,608 meters Rate of Fire . The M252 system . (2) Burn all dead grass or brush within 30 meters around the burning place. The term "indirect fire" means firing at an enemy without having a. Weights (pounds) System (including basic issue items) Barrel (with blast attenuator device) Mount M3A1 Baseplate M252A1 81mm Mortar: Maximum Range (meters): 5,935; Ammunition: War reserve HE (M821A3), red phosphorus smoke (M819), visible light illumination (M853A1), infrared illumination (M816), war reserve and training HE (M889A4), and FRP . Excess increments should not accumulate near the mortar positions but are removed to a designated place of burning and destroyed. Finally, the assistant gunner loosens the leg-locking handwheel, presses the spring-loaded locating catch, and raises the plain leg behind the buffer cylinders until it touches the traversing handwheel. f. The open end of the socket must continue to point in the direction of fire. It has no safety pins or wires to reduce preparation time. It has a time setting of up to 25 seconds. These cartridges are used first in subsequent firing so that once-opened stocks can be kept to a minimum. If it gets wet or dirty, it must be wiped off at once. News. There must not be a visible gap between the fuze and cartridge body. The superior flow characteristics of these BALL POWDER . Ammunition is made and packed to withstand all conditions ordinarily encountered in the field. This round may be stored in a horizontal position. 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 . (3) The securing strap is correctly located, securing the barrel clamps and buffers to the plain leg. 81MM M252A1. The assistant gunner checks the bipod and ensures that--. b. They are assembled with either an M524-series, M526-series, or M567 fuze. The first ammunition bearer holds the barrel until the assistant gunner has removed the mount. b. These fuzes use a clockwork mechanism to delay functioning for a specific time. It comes preset to function on SQ/IMP, and the selector slot should align with the SQ mark on the ogive. a. The components of the mortar consist of a canon, sight, mount, and baseplate. b. c. Crest Clearance. The M751 is fitted with a smoke charge that operates on impact. This may cause the firing pin to ignite the charges if the cartridge is dropped on the fin end (. 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. (1) The M935 fuze has two function settings: impact and delay. SQUAD AND SECTION ORGANIZATION AND DUTIES, Each member of the infantry mortar squad has principle duties and responsibilities. The mortar is within two turns of center of traverse. The mortar also offered the promised increase in range as well, allowing fire teams to engage the enemy at distance. It is fitted with a safety wire and pin that are removed immediately before firing. The body is made of aluminum and brass. It can be set from 3 to 55 seconds at half-second intervals. The propelling charge consists of an ignition cartridge and removable propellant increments. They use the M5 propelling charge that consists of eight cloth bags attached to the tail unit. (3) The M84A1 fuze is a single-purpose, tungsten-ring, mechanical-time fuze used with the 81-mm M301A3 illumination cartridge. The BAD is removed only by qualified maintenance personnel. The powder increments, mainly, should not be exposed to direct sunlight. An official website of the United States government. The gunner then kicks the barrel several times with his heel in an attempt to dislodge the round. 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, lays the mortar for elevation, and traverses onto the aiming post by turning the traversing handwheel and adjusting nut in the same direction. Ammunition Lot Number. 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 cartridge is painted olive drab with yellow markings. The assistant gunner attempts to maintain the traversing mechanism on a horizontal plane. This section contains information on how to prepare the 81-mm mortar, M252, for firing, how to conduct safety checks, and, if a misfire should occur during firing, what actions the crew applies to remove the cartridge from the barrel. The M375 cartridge uses the M90 propelling charge while the M375A2 and M375A1 cartridges use the M90A1 propelling charge. It uses the M219 propelling charge and weighs about 9.1 pounds. The equipment is placed out the same as for the gunner's examination (Chapter 9). Red phosphorus rounds can be fired from the M29/M29A1 at a reduced charge (maximum charge = charge 2). The types of fuzes described in this paragraph are point detonating, proximity, mechanical time, multioption, and dummy. The M1 was a derivative of the French mle 27/31 system (itself an improved form of the Stokes Trench Mortar of World War 1 fame) and slightly altered to suit American needs. Training practice is used only for training. (See FM 7-90 for a discussion of the duties of the platoon headquarters.). The air burst over average types of soil ranges from 1 to 6 meters, depending on the angle of approach. The explosive elements in primers and fuzes are sensitive to shock and high temperature. Then he relocks the barrel clamp. The standard infantry support weapon is the M-252 81mm mortar, which lobs a 10 lb. 1:4 For the 81MM Mortar System: X NSN (LIN): 1015-01-441-3113 : STAFF SECTION, CLEANING, ARTILLERY 1:4: The mount consists of elevating and traversing mechanisms and a bipod (Figure 4-4). The cannon assembly consists of the barrel that is sealed at the lower end with a removable breech plug, which houses a removable firing pin (Figure 4-3). However, since explosives are affected by moisture and high temperature, they must be protected. Other armies count on 81mm mortar families. Fired . Dropping may cause the propellant charges to ignite, causing bodily injuries. The M252 medium mortar offers a compromise between the light and heavy mortars. To set for delay, the selector slot should be rotated clockwise until it is aligned with the "D" mark on the ogive. FT 81-AI-3 Firing Tables Mortar, 81mm: M28A1 and M29 Mortar 81mm Self propelled M125A1 and M125 Carrier, 81mm Mortar Tracked XM755 In addition to supervising the emplacement, laying, and firing of the mortar, he supervises all other squad activities. A locked padlock ) or https:// means youve safely connected to the .gov website. The cartridge is painted olive drab with yellow markings and weighs about 9.05 pounds. The first ammunition bearer shakes the barrel to dislodge any remnants from the last round fired, and he lowers the barrel into the rotating socket of the baseplate. If not, the cartridge is placed on its side, and the closing plug is removed using an M18 fuze wrench. Several types of RP/WP ammunition are described herein. All mortar cartridges are painted to prevent rust and to identify their type. This ensures a maximum traversing and elevating capability after making the movement. He places his thumbs alongside the forefingers, being careful to keep both hands away from the muzzle. At the command, MARCH ORDER, the squad places the mortar, equipment, and ammunition in the squad vehicle and trailer. An air cavity can form on one side of a cartridge to unbalance it, causing instability in flight. The M252 81mm mortar is a smooth-bore, muzzle-loaded, high-angle-of-fire weapon. The squad leader indicates the direction of fire when mounting. The 81mm mortar is a portable, mobile, medium mortar at the infantry's disposal. . The components of the mortar consist of a cannon, mount, and baseplate. b. . As soon as the sight data are announced, the gunner places it on the sight. d. The gunner removes the sight from its case, mounts it on the mortar, and sets a deflection of 3200 mils and an elevation of 1100 mils. Types of rounds, classification, and characteristics for the 81-mm mortar, M252. The striker has been modified to be able to use German and Italian patterns of 81mm mortar . Cartridges assembled with the M532 fuze must be fired above charge 0. c. Upon receiving the command REFER, REALIGN AIMING POST, two actions take place at the same time in the mortar squad. The gunner checks the baseplate and ensures that--. Training practice--M879, M880, M68, and sabot. Types of rounds, classification, and characteristics for the 81-mm mortar, M29A1 (Standard B for the 81-mm mortar, M252). Identification. Attached to the right of the screw is the traversing handwheel. The mortar is then re-laid on the aiming posts using the traversing crank. The M889 HE cartridge (M252 onlyXUS Marine Corps) is of the same construction as the M821 cartridge in every detail except the fuze, which is the M935. They are fuzed with the M524-series, M256-series, or M532. The cartridge is painted light green with black markings and one narrow brown band. They are painted light green with red markings and one narrow yellow band. Additional information is included on an ammunition data card inside each container. At the muzzle end is a cone-shaped blast attenuator device (BAD) that is fitted to reduce noise. The removable increments are fitted onto or around the shaft, depending on their type. Mount The mortar should be within two turns of center of traverse when the task is compete. The assistant gunner exposes 8 inches (200 millimeters) of elevation shaft, leaving the elevation handwheel unfolded. I have included my order history, detailed photos, as well as my personal opinion on International Military Antiques, IMA -USA www.ima-usa.com 81mm Display Mortar that they have for sale. He must not stand directly behind the mortar. Table 4-3. All elements given in the fire command are repeated by the squad. The vertical cross line of the sight is on the left edge of the aiming point. If, upon removal of the safety wire, a buzzing sound in the fuze is heard, the round should not be used. Several types of HE ammunition are used in the 81-mm mortar, M252. It is a smooth-bore, muzzle-loading, high-angle-of-fire weapon used for long-range indirect fire support to light infantry, air assault, and airborne units across the entire front of a battalion zone of influence. (5) Four inches of elevation shaft are exposed, and the shaft is not bent. An ammunition lot number is assigned to each ammunition lot, which is marked on each cartridge and packing container. TM - Technical Manuals (Range 9) TM - Technical Manuals (Range 10) TM - Technical Manuals (Range 11-4) TM - Technical Manuals (Range 11-5) . He moves the mortar until the vertical line of the sight is aligned approximately on the aiming post. b. e. The squad leader picks up the aiming posts and sight. It can provide all-weather, ground-based, close supporting, accurate, immediately The 81mm mortar rounds use Red Phosphorus as the smoke generating agent. The M821/M889 are 81mm HE Mortar Cartridges. This cartridge is ballistically matched to the M374A2, M374A1, and M375 HE cartridges, and weighs about 9.12 pounds. If the primer is not dented, the round may be used again. d. When the barrel reaches the horizontal position, and not before, the assistant gunner moves the thumb of each hand over the muzzle. The cartridge must not be fired below charge 3. He opens the cross-level handwheel, traversing handwheel, and barrel clamp. When the fuze of the misfired round reaches the BAD, the assistant gunner stops the round with his thumbs (he does not touch the fuze) and carefully removes it from the barrel. . b. a. .50 MACHINE GUN, M3; FIRING CARTRIDGE, CAL. (b) In selecting the exact mortar position, the leader looks quickly for mask clearance and overhead interference. As a longstanding partner of armed forces around the globe, Rheinmetall supplies a wide array of mortar systems and ammunition. 107 Army Pentagon d. Multioption. 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. c. Mechanical Time. When fired, the cartridge carries the ignition cartridge with it, leaving the mortar ready for the next cartridge. Joint Tables of Allowance; PB - Professional Bulletins; STP - Soldier Training Publications; TC - Training Circulars; . If the line of sight clears the mask, it is safe to fire. It provides illumination for about 60 seconds with 600,000 candlepower illumination. There is a selector on the lower shaft for non-delay or delay impact action. This document (FT 81 B3, abridged) consists of two pages, each with a separate table. High explosive--M821, M889, M374-series, and M362. The platoon leader commands the platoon and supervises the training of the elements. 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) . The sight bracket is attached to the buffer carrier, which is fitted to the traversing screw assembly. The M375A3 cartridge is ballistically similar to the M374A3 (HE) cartridge. The wrench (P/N 9349539) sets M772 MT and M768 time fuzes. .30 BROWNING, M1917 AND M1917A1; GUN, MACHINE, CAL. If not, he may still fire at the desired range by selecting a charge zone having a higher elevation. (8) To help minimize the occurrence of short rounds and or duds, unpackaged ammunition that has been dropped should not be fired. All rounds are colored according to their type. If the fuze does not function as set, it automatically functions at the next lower setting. When the gunner is satisfied with his sight picture he announces, "Up.". Target terrain, such as ice and dry sand, gives lowest burst heights, whereas water and wet ground give highest burst heights. The fuze is nicely marked and is dated 1940. b. The 81mm weapons platoon consisted of the headquarters platoon and four mortar squads. Each squad member should be able to perform all the following premount checks: a. To make the shift, the gunner places the fingers of his right hand in the muzzle and his left hand on the left leg. The leg-locking handwheel must then be tightened, ensuring the teeth are correctly meshed. Once set to act as an impact fuze, the mechanism cannot be reset for PROX. c. The elevating shaft is contained in the elevating leg; to the left of the elevating leg is the elevating handwheel. Lock 4-4. a. Overhead interference can be branches of trees or roofs of buildings. To convert the fuze from PROX to SQ/IMP, the top of the fuze must be rotated 120 degrees (one-third turn) in either direction. Each cartridge weighs about 10 pounds and is provided with the M223 propelling charge, consisting of four horseshoe-shaped increments fitted around the tail. All PD fuzes are superquick--detonate on impact. (1) Marking on container. Powered by Hugo. It is constructed from ductile cast iron and contains about 1.5 pounds of cyclonite (RDX)/trinitrotoluene (TNT) composition explosive. When firing under the control of an FDC, he reports to the FDC that mask clearance cannot be obtained at a certain elevation. It contains white phosphorus that produces white smoke on contact with air. Figure 4-4. The squad leader notifies the FDC of the minimum mask clearance elevation. If water is not available, the gunner must stand clear of the mortar until the barrel is cool. M3A1 Baseplate The fuze body is graduated from 0 to 50 seconds in 2-second intervals; 10-second intervals are indicated by bosses. .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. Army Publishing Directorate This section implements STANAG 2321 and QSTAG 900 (Edition 1). Developed by Hirtenberger Defence Systems (HDS), the rugged and reliable M8 comprises an 81 mm long-range weapon available in different barrel lengths, an entire range of ammunition, auxiliary field equipment, sighting systems and a fully digital fire-control system containing all ballistic data. The propelling charge is contained in four horseshoe-shaped, felt-fiber containers or nine wax-tested, cotton cloth, bag increments. d. The gunner rough levels the cross-level bubble by making the bubble bounce from one side to the other. f. Ammunition should be stored under cover. 4-10. The fuze body is graduated from 0 to 25 seconds in 1-second intervals; 5-second intervals are indicated by bosses. The squad leader picks up the sight case and the two aiming posts, and moves to the exact position where the mortar is to be mounted. 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 . The M252 81 mm medium weight mortar is a British-designed smooth bore, muzzle-loading, high-angle-of-fire weapon used for long-range indirect fire support to light infantry, air assault, and airborne units across the entire front of a battalion zone of influence. He makes large deflection shifts by shifting the bipod assembly and keeps the bubbles level during firing. Red phosphorus/white phosphorus is used for screening, producing casualties, creating incendiary effects, and signaling. When targets are beyond such irregularities, a clearance of at least 30 meters should be allowed to ensure maximum effect over the target area. The M819 cartridge (M252 only) has a cylindrical body and contains red phosphorus that produces white smoke on contact with air. The tabulated data of the 81-mm mortar, M252, are shown in Table 4-1. The term "danger close" is included in the call for fire when there are friendly troops or positions within a prescribed distance of the target, specifically 600 meters for artillery or mortars . 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. Check the post SOP before applying the following procedure: (1) Select a place at least 100 meters from the mortar position, parked vehicles, and ammunition piles. (2) The fin and fuze assembly must be checked for tightness and damage. Do not burn increments in piles but spread them in a train 1 to 2 inches deep, 4 to 6 inches wide, and as long as necessary. General Dynamics Ordnance and Tactical Systems is the leading manufacturer of propellants for 60mm, 81mm and 120mm Mortar Systems. b. The gunner is given a deflection change between 5 and 25 mils, either increasing or decreasing from the last stated deflection, and the command to refer and realign aiming posts. The M301A3 cartridge has a cylindrical body that contains an illuminating candle and parachute assembly. M64A1 Sightunit. In any case, the gunner must ensure that the cartridge does not strike an obstacle. The company level vehicles also carry a vehicle-mounted 120mm mortar, which is augmented by the 60mm M224 mortar for dismounted use. e. The M362A1 and M362 HE cartridges are of steel forge construction and contain about 2.10 pounds of composition B explosive. The mortar is within two turns of center of traverse. He is also the squad driver. This round must be stored in a vertical position. (e) If the mask is not regular throughout the sector of fire, the gunner determines the minimum mask clearance as described above. Those cartridges assembled with the M524 (A1, A2, A3, or A4) fuze are for use by the US Marine Corps and US Navy only. Swifty 3 from scratch; Swifty 3 split-repo setup; Swifty Troubleshooting; Mods. b. A securing strap is attached to the plain leg for securing the bipod in the folded position. He positions the lower barrel clamp against the lower stop band on the barrel and secures the upper barrel clamp. It is assembled with the M772A1 MTSQ. The baseplate (Figure 4-5) is of one-piece construction, and supports and aligns the mortar for firing. c. The assistant gunner disengages the barrel clamps and moves the bipod from the immediate area of the mortar position. c. The first ammunition bearer checks the barrel and ensures that--. The traversing screw assembly is fitted to the clamp assembly, which is pivoted in the center on an arm attached to the elevating leg. Complete cartridges are always handled with care. He indicates the initial direction of fire by pointing in that direction and commands ACTION. The M821 HE cartridge (M252 only) is a British-made cartridge fitted with the US M734 multioption fuze. d. The squad leader supervises the squad drill and is responsible for supervising the laying out of the equipment as shown in Figure 4-6. A proximity fuze is an electronic device that detonates a projectile by means of radio waves sent out from a small radio set in the nose of the projectile. See Chapter 3, paragraph 3-14 for a detailed discussion of malfunctions. Ammunition is typed according to use (Table 4-2). (a) Since the mortar is normally mounted in defilade, there could be a mask such as a hill, tree, building, or rise in the ground. (1) The barrel is clean and free from grease and oil both inside and out. The M853 cartridge (M252 only) has a cylindrical body that contains an illuminating candle and parachute assembly. Remaining increments are repositioned towards the rear of the tail fin assembly when firing the cartridge with horseshoe-shaped increments at less than full charge. The fuze should already be fitted to the cartridge. 0.50, BROWNING, M2; FIRING CARTRIDGE, ARMOR-PIERCING-INCENDIARY, CAL. While the assistant gunner supports the barrel, the gunner slackens the leg-locking handwheel, releases the locating catch, and positions the plain leg. It is light enough to be portable when broken down into. (2) The barrel is locked to the baseplate, and the open end of the socket points in the direction of fire. ), FIRING TABLES FOR, CANNON, 155MM, HOWITZER, M185 ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, 109A1 HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, 109A1B HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A2 HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A3 HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A3B AND HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, 109A4 AND CANNON, 155MM, HOWITZER, M284 ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, 109A5 AND HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, 109A6 AND CANNON, 155MM, HOWITZER, M199 ON HOWITZER, MEDIUM, TOWED, 155MM, M198 AND CANNON, 155MM, HOWITZER, XM776 ON HOWITZER, MEDIUM, TOWED, 155MM, XM777 FIRING PROJECTILE, HE, M795 (S&I BY PROP SEE DETAILS, FOOTNOTES), FIRING TABLES FOR 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, SMOKE, WP, M1121 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 FOOTNOTES). He places the sight case and aiming posts to the left front of the mortar position. Mortars are indirect-fire weapon systems. The safety/packing clip should be removed when the cartridge is unpacked. 120mm IHE grenade DM91. A spring-loaded locating catch is behind the elevating gear housing, which locates the plain leg in its supporting position for level ground. He has the duty of preparing the ammunition and passing it to the assistant gunner. 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.] In charge was the platoon commander - normally a lieutenant. During training, the gunner may use the driving stake from the aiming post case. Its range and explosive power is greater than the M224, yet it is still light enough to be man . The round has a burst height of 600 meters and provides illumination for about 60 seconds for an area of about 1,200 meters. A .mil website belongs to an official government organization in the United States. b. .50: BROWNING, M2 (HEAVY BARREL, FLEXIBLE) ON MOUNT, MACHINE GUN, TRIPOD MTD, CAL. b. c. The gunner grasps both ends of the traverse screw assembly and supports the mortar during the subsequent drill. DESCRIPTION. d. The M374A2, M374A1, and M374 HE cartridges are painted olive drab with yellow markings and are constructed from pearlitic malleable cast iron. Fort Belvoir, VA 22060 The adjustment ring has six raised ribs for use in conjunction with fuze setter, M25, and a setting indicator rib (marked SET) about half the height and width of the other six ribs. Disposal Precautions. If he is not within 20 mils, the gunner and assistant gunner must make another large shift before moving on.