81mm mortar range table

a. Before-firing checks include the following: (1) Ammunition should be free of moisture, rust, and dirt. If the fuze does not function as set, it automatically functions at the next lower setting. It has no safety pins or wires to reduce preparation time. The propelling charge is contained in four horseshoe-shaped, felt-fiber containers or nine wax-tested, cotton cloth, bag increments. The fuze threads and fuze well threads are inspected for damage. The M821A2/821A1/889A1 consists of the following major components: M935 Point Detonating Fuze or M734/734A1 Multi-Option Fuze. It should be destroyed in accordance with standard procedures. e. The gunner centers the elevation bubble. b. 81mm smoothbore mortar Barrel length 1.28 m Muzzle velocity 225 m/s Elevation +45 to +85 Traverse 18 Fire control Sights C2 indirect fire sight with illumination Firepower Rate of fire 20 rpm maximum 15 rpm normal 1 to 12 rpm sustained Range 5.650 m maximum 100 m minimum Media 81mm L16A2 b. Since phosphorus liquefies at about 100 degrees Fahrenheit, the ammunition is protected against an uneven rehardening of the filler. d. Climatic Effects. 4-11. The gunner places the outer edge of the baseplate against the baseplate stake so that the left edge of the cutaway portion of the baseplate is aligned with the right edge of the stake (Figure 4-7). c. Mechanical Time. As soon as the sight data are announced, the gunner places it on the sight. The types of fuzes described in this paragraph are point detonating, proximity, mechanical time, multioption, and dummy. (See FM 7-90 for a discussion of the duties of the platoon headquarters.). General Dynamics Ordnance and Tactical Systems is the leading manufacturer of propellants for 60mm, 81mm and 120mm Mortar Systems. They are fuzed with the M524-series, M256-series, or M532. It uses the M185 propelling charge that consists of eight increments fitted into the spaces between the fins and held by a propellant holder. The assistant gunner cleans the bore and swabs it dry. b. He has the duty of preparing the ammunition and passing it to the assistant gunner. 120mm IHE grenade DM91. In any case, the gunner must ensure that the cartridge does not strike an obstacle. Proximity-fuzed short cartridges, which are duds, contain a complete explosive train and impact element. A plain leg is fitted to a stud on the elevating leg and is secured by a leg-locking handwheel. Identification. The fuze body is graduated from 0 to 50 seconds in 2-second intervals; 10-second intervals are indicated by bosses. To dismount the mortar, the squad leader commands, OUT OF ACTION. 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. It is constructed from ductile cast iron and contains about 1.5 pounds of cyclonite (RDX)/trinitrotoluene (TNT) composition explosive. d. The ammunition is protected from mud, sand, dirt, and water. (4) The bipod locking latch is locked, securing the barrel clamps. .50: BROWNING, M2 (HEAVY BARREL, TURRET TYPE) ON MOUNT, MACHINE GUN, TRAILER MTD: MULTIPLE CAL. End this starting train with not less than 1 meter of inert material (dry grass, leaves, or newspapers). 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. When set at delay, the fuze train causes a 0.05-second delay before functioning. They use the M5 propelling charge that consists of eight cloth bags attached to the tail unit. Both the 60mm and 120mm mortar rounds use White Phosphorus. If the mortar section is to operate quickly and effectively in accomplishing its mission, mortar squad members must be proficient in individually assigned duties. It can be fitted with either the M567, M524, or M532-series fuzes. b. Proximity fuzes withstand normal handling without danger of detonation or damage when in their original packing containers or when assembled to projectiles in their packing containers. e. The M362A1 and M362 HE cartridges are of steel forge construction and contain about 2.10 pounds of composition B explosive. The M374 cartridge is fitted with the M90 propelling charge. f. If the above procedure fails to remove the misfire, the barrel must be kept horizontal. At the muzzle end is a cone-shaped blast attenuator device (BAD) that is fitted to reduce noise. (703) 614-3727, Office of the Chief Information Officer Powered by Hugo. M252 81mm Mortars The M252 81mm medium extended range mortar (see diagram below) is a crew-served, smooth bore, muzzle loaded, high angle of fire weapon system. Types of rounds, classification, and characteristics for the 81-mm mortar, M29A1 (Standard B for the 81-mm mortar, M252). As a longstanding partner of armed forces around the globe, Rheinmetall supplies a wide array of mortar systems and ammunition. The following are authorized (Standard B) cartridges for the 81-mm mortar, M252: Each cartridge has fins around the tail to stabilize it in flight and to cause it to strike fuze-end first. It uses the M772 mechanical time fuze and weighs about 10.6 pounds. In the U.S. Army and U.S. Marine Corps, it is normally deployed in the mortar platoon of an infantry battalion. The first table is a chart that shows range and elevation for firing particular mortar shells. Washington DC 20310-0107, ADRP - Army Doctrine References Publications, ATTP - Army Tactics, Techniques, and Procedures, FY Publication Status Report (CAC required for access), Publishing Resources (CAC required for access), PC/PCO/FMO/EPCO Directory (CAC required for access), usarmy.pentagon.hqda-apd.mbx.customer-service@army.mil, GUN, MACHINE, CAL. Mount, M177, in folded position. Each squad member should be able to perform all the following premount checks: a. High angles of approach (near vertical) give the lowest burst heights. on Amazon.com. It is used for records such as reports on condition, malfunctions, and accidents. It uses the M219 propelling charge and weighs about 9.1 pounds. 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. At the same time, the first ammunition bearer moves out on the double to realign the aiming posts. These fuzes use a clockwork mechanism to delay functioning for a specific time. He lays for deflection, taking the proper sight picture. (2) Burn all dead grass or brush within 30 meters around the burning place. The squad leader notifies the FDC of the minimum mask clearance elevation. Short cartridges can be expected when firing below charge 4. The mortar is within two turns of center of traverse. Several types of RP/WP ammunition are described herein. The components of the mortar consist of a cannon, mount, and baseplate. The gunner removes the sight and places it in the case with 3200 deflection and 0800 elevation indexed. (1) The M772A1 fuze is a MTSQ. The propelling charge consists of an ignition cartridge and removable propellant increments. (6) The primer cartridge is checked for damage or dampness. Safety before firing is provided by a safety wire, which must be removed just before firing. The 81mm weapons platoon consisted of the headquarters platoon and four mortar squads. It has two types: type 1 resembles the M734 fuze, and type 2 resembles the M935 fuze. d. The gunner recovers the baseplate to the area designated by the squad leader. The explosive elements in primers and fuzes are sensitive to shock and high temperature. Table 4-1. 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 increments are individually wrapped with waterproof bags that are not removed. If the primer is not dented, the round may be used again. The standard infantry support weapon is the M-252 81mm mortar, which lobs a 10 lb. There is a selector on the lower shaft for non-delay or delay impact action. a. The bipod provides front support for the barrel and carries the gears necessary to lay the mortar. The M532 fuze is a radio doppler fuze that has a proximity (PROX) or SQ/IMP function. He levels all bubbles. The M252 81mm mortar is a smooth-bore, muzzle-loaded, high-angle-of-fire weapon. The sight bracket is attached to the buffer carrier, which is fitted to the traversing screw assembly. (1) Mask clearance and overhead clearance are sufficient. The assistant gunner exposes 8 inches (200 millimeters) of elevation shaft, leaving the elevation handwheel unfolded. The term "indirect fire" means firing at an enemy without having a. The muzzle end has a short tapered lead-in which acts as a . The gunner is given an administrative command to lay the mortar on a deflection of 2860 or 2740 mils. 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. If it gets wet or dirty, it must be wiped off at once. The firing pin must be replaced and the bore swabbed. How the RCGM works: Target coordinates are programed into the RCGM using a portable GPS setter. If it is necessary to leave the ammunition uncovered, it should be raised on dunnage at least 6 inches above the ground. It is fitted with a standard pull wire and safety pin that are removed immediately before firing. b. Then it is removed from the bipod and laid horizontally on the ground at the dud pit until it can be turned over to ordnance personnel. Placing the mortar in position at night does not relieve the gunner of the responsibility of checking for mask clearance and overhead interference. It is light enough to be portable when broken down into. The M751 fuze is the only dummy fuze used with the 81-mm mortar. SQUAD AND SECTION ORGANIZATION AND DUTIES, Each member of the infantry mortar squad has principle duties and responsibilities. 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. When fired, the cartridge carries the ignition cartridge with it, leaving the mortar ready for the next cartridge. Secure .mil websites use HTTPS c. The first ammunition bearer checks the barrel and ensures that--. The gunner stands to the left side of the mortar where he can manipulate the sight, elevating handwheel, and traversing handwheel. Theme by TechDoc. 1:4 For the 81MM Mortar System: X NSN (LIN): 1015-01-441-3113 : STAFF SECTION, CLEANING, ARTILLERY 1:4: The superior flow characteristics of these BALL POWDER . They function normally in light rain; however, heavy rain, sleet, or snow can cause an increase in the number of early bursts. The M375A3 cartridge is ballistically similar to the M374A3 (HE) cartridge. . Burst Height. The round is still safe to handle and transport if the safety wire is reinserted. If not, the cartridge is placed on its side, and the closing plug is removed using an M18 fuze wrench. b. .50: BROWNING, M2 (HEAVY BARREL, FLEXIBLE) ON MOUNT, MACHINE GUN, TRIPOD MTD, CAL. The ignition cartridge (with primer) is fitted into the base of the fin shaft. I say 120s are bad because they suffer from terrible dispersion even when not shooting at 6km. b. MFCS Mounted. If the line of sight clears the mask, it is safe to fire. The gunner should expose 6 inches (150 millimeters) of elevation shaft and center the buffer carrier. Figure 4-4. Official websites use .mil A safety latch located at the side of the recess is used to secure the ball. A lock ( The settings are obtained from the range tables and are applied using a wrench (number 9239539) or a 1 3/4-turn open-end wrench. An ammunition lot number is assigned to each ammunition lot, which is marked on each cartridge and packing container. More uniform firing is obtained if ammunition is kept at the same temperature. An official website of the United States government. f. The open end of the socket must continue to point in the direction of fire. The traversing screw assembly is fitted to the clamp assembly, which is pivoted in the center on an arm attached to the elevating leg. The propellant train (except the training cartridge) consists of an ignition cartridge and propellant charges. The squad leader indicates the direction of fire when mounting. The M301A3 cartridge has a cylindrical body that contains an illuminating candle and parachute assembly. 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. High explosive--M821, M889, M374-series, and M362. After the barrel cools, the gunner removes the sight and firing pin. The cartridge is painted light green and has red markings and one narrow yellow band. a. ), FIRING TABLES FOR 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 AND HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A4 AND CANNON, 155MM HOWITZER, M284 ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A5 AND HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A6 AND CANNON, 155MM HOWITZER, M199 ON HOWITZER, MEDIUM, TOWED, 155MM, M198 AND CANNON, 155MM HOWITZER, M776 ON HOWITZER, MEDIUM, TOWED, 155MM, M777A1 FIRING PROJECTILE, HE, M483A1 (S&I BY PROP SEE DETAILS, FOOTNOTES), 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, M776 ON HOWITZER, MEDIUM, TOWED, 155MM, M777A1 FIRING PROJECTILE, HERA, M549 PROJECTILE, HERA, M549A1 (S&I BY PROP SEE DETAILS, FOOTNOTES), FIRING TABLES FOR 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, HERA, M549 AND PROJECTILE, HERA, M549A1 (S&I BY PROPONENT, SEE DEAILS, FOOTNOTES. Once set to act as an impact fuze, the mechanism cannot be reset for PROX. The following safety checks must be enforced before firing the mortar. This ensures a maximum traversing and elevating capability after making the movement. Light tree foliage and light vegetation affect the height of burst only slightly, but dense tree foliage and dense vegetation increase the height of burst. e. The squad leader picks up the aiming posts and sight. FIRING TABLE FOR 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; AND HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A3B; AND CANNON, 155MM HOWITZER, M284 ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A5 AND HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A6 AND CANNON, 155MM HOWITZER, M199 ON HOWITZER, MEDIUM, TOWED, 155MM, M198 FIRING PROJECTILE, GUIDED, M712 (COPPERHEAD) WITH SHAPED TRAJECTORIES (S&I BY PROP SEE DETAILS, FOOTNOTES), PROVISIONAL AIMING DATA FOR CANNON, 155MM, HOWITZER, M185 ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, 109A1 HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, 109A1B HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A2 AND HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A3 HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A3B AND HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A4 AND CANNON, 155MM HOWITZER, M284 ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A5 AND HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A6 AND CANNON, 155MM HOWITZER, M199 ON HOWITZER, MEDIUM, TOWED, 155MM, M198 AND CANNON, 155MM HOWITZER, M776 ON HOWITZER, MEDIUM, TOWED, 155MM, M777A1 FIRING PROJECTILE, BASE-BURN, M864 AND M864A1 (S&I BY PROP SEE DETAILS, FOOTNOTES), PRELIMINARY AIMING DATA FOR CANNON, 155MM HOWITZER, M284 ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A6 AND CANNON, 155MM HOWITZER, M776 ON HOWITZER, MEDIUM, TOWED, 155MM, M777A2 FIRING PROJECTILE, HE, XM982 (S&I BY PROP SEE DETAILS, FOOTNOTES), PROVISIONAL AIMING DATA FOR CANNON, 155MM HOWITZER, M284 ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A6 AND CANNON, 155MM HOWITZER, M776 ON HOWITZER, MEDIUM, TOWED, 155MM, M777A2 FIRING PROJECTILE, HE, XM982 (S&I BY PROP SEE DETAILS, FOOTNOTES), PROVISIONAL AIMING DATA FOR CANNON, 155MM HOWITZER, M284 ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A6 AND CANNON, 155MM HOWITZER, M776 ON HOWITZER, MEDIUM, TOWED, 155MM, M777A2 FIRING PROJECTILE, HE, M982 (S&I BY PROP SEE DETAILS, FOOTNOTES), CANNON, 165-MM GUN, M135 ON COMBAT ENGINEER VEHICLE, FULL TRACKED, M728; FIRING CARTRIDGE, 165-MM, HEP, M123A1 AND 165-MM, TP-T, XM623 (S&I BY PROP SEE DETAILS, FOOTNOTES), CANNON, 175-MM GUN, M113 AND M113A1 ON GUN, FIELD ARTILLERY, SELF-PROPELLED: 175-MM, M107; FIRING PROJECTILE, HE, M437A2 AND M437A1 (S&I BY PROP SEE DETAILS, FOOTNOTES), RAPID FIRE TABLES FOR CALCULATION OF THE EXECUTIVE OFFICERS (XOS) MINIMUM QUADRANT ELEVATION WITH CANNON, 105MM HOWITZER, M20A1 ON HOWITZER, LIGHT, TOWED, 105MM, M119A1; HOWITZER, LIGHT, TOWED, 105MM, M119A2; HOWITZER, LIGHT, TOWED, 105MM, M119A3 FIRING WITH PROPELLING CHARGES, M67 AND M200 (S&I BY PROP SEE DETAILS, FOOTNOTES), RAPID FIRE TABLES FOR CALCULATION OF THE EXECUTIVE OFFICER S (XO S) MINIMUM QUADRANT ELEVATION WITH CANNON, 155MM HOWITZER, M284 ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A5/A6 AND CANNON, 155MM HOWITZER, M199 ON HOWITZER, MEDIUM, TOWED, 155MM, M198 AND CANNON, 155MM HOWITZER, M776 ON HOWITZER, MEDIUM, TOWED, 155MM, M777A1/A2 FIRING WITH PROPELLING CHARGES, M231, M232, AND M232A1 (S&I BY PROP SEE DETAILS, FOOTNOTES), RAPID FIRE TABLES FOR CALCULATION OF THE EXECUTIVE OFFICERS (XOS) MINIMUM QUADRANT ELEVATION WITH CANNON, 155MM HOWITZER, M284 ON HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A5; HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A6; AND HOWITZER, MEDIUM, SELF-PROPELLED, 155MM, M109A7, AND CANNON, 155MM HOWITZER, M776 ON HOWITZER, MEDIUM, TOWED, 155MM, M777A1 AND HOWITZER, MEDIUM, TOWED, 155MM, M777A2 FIRING WITH PROPELLING CHARGES, M231, M232, AND M232A1 (S&I BY PROPONENT, SEE DETAILS, FOOTNOTES), ADDENDUM TO FTR LANCE-B-1 FOR WARHEAD SECTION, GUIDED MISSILE, HE: M251 (U) (S&I BY PROP SEE DETAILS, FOOTNOTES), Search Army publications and forms by Number, Title, or Record Detail. In charge was the platoon commander - normally a lieutenant. The M821 HE cartridge (M252 only) is a British-made cartridge fitted with the US M734 multioption fuze. The M252 system . (4) The M567 fuze is an impact fuze that has a SQ/IMP or D function. 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. d. The M374A2, M374A1, and M374 HE cartridges are painted olive drab with yellow markings and are constructed from pearlitic malleable cast iron. He tightens the leg-locking handwheel (ensuring the teeth are correctly meshed) and fastens the securing strap over the arm and around the buffers. 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 company level vehicles also carry a vehicle-mounted 120mm mortar, which is augmented by the 60mm M224 mortar for dismounted use. The mortar is then re-laid on the aiming posts using the traversing crank. The gunner then kicks the barrel several times with his heel in an attempt to dislodge the round. All rounds are colored according to their type. The M375 cartridge uses the M90 propelling charge while the M375A2 and M375A1 cartridges use the M90A1 propelling charge. When the approximate alignment is completed, the gunner signals the assistant gunner to lower the bipod by pushing down on the mortar. Table 4-3. This round must be stored in a vertical position. If water is not available, the gunner must stand clear of the mortar until the barrel is cool. The principal factors affecting height of burst are the angle of approach to the target and the reflectivity of the target terrain. The mortar should be within two turns of center of traverse when the task is compete. The gunner is given a deflection change in a fire command between 20 and 60 mils inclusive. Mortars are indirect-fire weapon systems. a. ) or https:// means youve safely connected to the .gov website. Red phosphorus cartridges (M252 only) are stored the same as HE cartridges. The cartridges are returned to their original containers. These propellants are flash-suppressed and clean burning resulting in minimum residue, flash and blast overpressure. The striker has been modified to be able to use German and Italian patterns of 81mm mortar . This document (FT 81 B3, abridged) consists of two pages, each with a separate table. CANNON . LHMBC. Red phosphorus/white phosphorus--M819 and M375-series. DESCRIPTION. Attached to the arm is the cross-leveling mechanism, which is attached to the clamp assembly at its upper end. 9301 Chapek Road., Bldg.1458 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. If the barrel is cool enough to handle, the crew removes the round as described below. The cartridge must not be fired below charge 3. 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. (3) The M256-series fuze has an SQ/IMP function only. Upon completion of any bipod movement on the barrel, the gunner ensures that the firing pin recess is facing upward. (2) The M84 fuze is a single-purpose, powder-train, mechanical-time fuze used with the 81-mm M301A1 and M301A2 illuminating cartridges. See Chapter 3, paragraph 3-14 for a detailed discussion of malfunctions. Dropping may cause the propellant charges to ignite, causing bodily injuries. (3) The M84A1 fuze is a single-purpose, tungsten-ring, mechanical-time fuze used with the 81-mm M301A3 illumination cartridge. Increments removed from cartridges before firing should be placed in a metal or wooden container located outside the firing vehicle/position at least 25 meters away. 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. To set for delay, the selector slot should be rotated clockwise until it is aligned with the "D" mark on the ogive. Army Publishing Directorate Lock All elements given in the fire command are repeated by the squad. The powder increments, mainly, should not be exposed to direct sunlight. 4-12. The cannon has a crew-removable breech plug and firing pin. The propelling charges are assembled around the fin assembly shaft. It comes preset to function on SQ/IMP, and the selector slot should align with the SQ mark on the ogive. Correctly applying and performing these duties enables the mortar section to perform as an effective fighting team. Share sensitive information only on official, secure websites. a. Cartridges are shipped with a complete propelling charge, an ignition cartridge, and primer. The ignition cartridge strikes the firing pin and detonates, which causes a flash that passes through the radial holes in the shaft. b. The fuze consists of a brass head, body assembly, and expelling charge. He exposes 4 inches (100 millimeters) of elevation shaft and folds the handle. c. After the gunner has announced, "Up," the squad leader should check the mortar to determine if the exercise was performed correctly. The tabulated data of the 81-mm mortar, M252, are shown in Table 4-1. 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. The fuze consists of a brass head, body assembly, and expelling charge. He may assist the gunner in shifting the mortar when the gunner is making large deflection changes. The components of the mortar consist of a cannon, mount, and baseplate. (c) The gunner determines mask and overhead clearance by sighting along the barrel with his eye near the breech plug. Firing tables are used to determine the correct charge for firing. The barrel is then rotated a quarter turn to unlock it from the socket, and it is placed in an area designated by the squad leader. 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. Its range and explosive power is greater than the M224, yet it is still light enough to be man . Range Minimum to maximum 83 to 5,608 meters Rate of Fire . 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. g. The barrel clamps can be moved along the barrel to counter large changes in elevation. c. The assistant gunner moves into position to the front of the bipod on his right knee and grasps the bipod legs (palms up), lifting until they clear the ground enough to permit lateral movement. The gunner is given a deflection and elevation change in a fire command causing the gunner to shift the mortar between 200 and 300 mils for deflection and between 100 and 200 for elevation. The fuzes may be used for day or night operations. 0.30, BROWNING, M1917A1; GUN, MACHINE: CAL. The M252 medium mortar offers a compromise between the light and heavy mortars. If not, he may still fire at the desired range by selecting a charge zone having a higher elevation. Bear in mind that these are my personal opinions, experiences, and . High explosive is used for both fragmentation and blast effect against personnel and light-skinned vehicles. All PD fuzes are superquick--detonate on impact. d. The gunner rough levels the cross-level bubble by making the bubble bounce from one side to the other. Then he relocks the barrel clamp. He must not stand directly behind the mortar. Propelling charges are covered or protected from dampness or heat. Any target that requires that elevation, or a lower one, cannot be engaged from that position. HE ammunition is used against personnel and materiel. *FREE* shipping on qualifying offers. M252 81mm Mortars The M252 81mm medium extended range mortar (see diagram below) is a crew-served, smooth bore, muzzle loaded, high angle of fire weapon system. This is the inert PD fuze type "IR-81" used by the Italians for their 81mm mortar rounds during WWII. The safety pull wire is removed just before inserting the cartridge into the mortar. 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 equipment is placed out the same as for the gunner's examination (Chapter 9). The RSTA squadron only receives the 120mm mounted mortar, there is no augmentation dismounted maneuvers. An 81 mm mortar is a medium-weight mortar. Despite its weight though, the 81mm mortar was an important part of the Table of Organization and Equipment of U.S. Army and U.S. Marine Corps maneuver battalions throughout World War II. b. d. When the barrel reaches the horizontal position, and not before, the assistant gunner moves the thumb of each hand over the muzzle. In addition to loading, he swabs the bore after 10 rounds have been fired or after each fire mission. News. Each cartridge weighs about 10 pounds and is provided with the M223 propelling charge, consisting of four horseshoe-shaped increments fitted around the tail. The ammunition that can be fired by the 81-mm mortar, M252, is identified and described herein. 60mm, 81mm, and 120mmMortar Increments. 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).

Sunspel Slim Fit Cotton Jersey T Shirt, Take Charge Of Your Life Sermon, Cummins Isx Egr Differential Pressure Sensor Location, Ticketmaster Fees Calculator, Articles OTHER