M252 mortar - Wikipedia Red phosphorus/white phosphorus--M819 and M375-series. 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 As a longstanding partner of armed forces around the globe, Rheinmetall supplies a wide array of mortar systems and ammunition. He maintains the ammunition for firing and provides local security for the mortar position. It is used for records such as reports on condition, malfunctions, and accidents. To dismount the mortar, the squad leader commands, OUT OF ACTION. 4-4. Army Publishing Directorate - Details Page d. Climatic Effects. Examples are: M3A1 Baseplate The cartridge must not be fired below charge 3. He uses the chain of command to assist him in effecting his command and supervising duties. It is painted white with black markings. If not, the cartridge is placed on its side, and the closing plug is removed using an M18 fuze wrench. Its range and explosive power is greater than the M224, yet it is still light enough to be man . The M252 system . It has a time setting of up to 50 seconds. The mortar should be within two turns of center of traverse when the task is compete. The cartridge uses the M205 propelling charge and is assembled with the M567 or M524-series fuze. I say 120s are bad because they suffer from terrible dispersion even when not shooting at 6km. f. Ammunition should be stored under cover. If the round fires, the mortar is re-laid on the aiming point and firing is continued. Safety before firing is provided by a safety wire, which must be removed just before firing. 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). LARGE DEFLECTION AND ELEVATION CHANGES. The gunner stands to the left side of the mortar where he can manipulate the sight, elevating handwheel, and traversing handwheel. g. The barrel clamps can be moved along the barrel to counter large changes in elevation. In addition to loading, he swabs the bore after 10 rounds have been fired or after each fire mission. Several types of HE ammunition are used in the 81-mm mortar, M252. They should not be approached for 5 minutes or disturbed for at least 30 minutes after firing. The fuze consists of a brass head, body assembly, and expelling charge. The cartridge can be fitted with the M524-series, M526-series, M567, or M532 fuzes. (3) The circlip is correctly located, securing the rotating socket to the baseplate. The components of the mortar consist of a cannon, mount, and baseplate. It is light enough to be portable when broken down into. To set for delay, the selector slot should be rotated clockwise until it is aligned with the "D" mark on the ogive. The M374A2 and M374A1 cartridges are fitted with the M90A1 propelling charge. e. Care, Handling, and Preservation. The assistant gunner checks the bipod and ensures that--. The wrench (P/N 9349539) sets M772 MT and M768 time fuzes. If the round does not fire, the gunner tests the barrel for heat. PDF Introduction to Crew Served Weapons B3m4078 Student Handout 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). The M751 is fitted with a smoke charge that operates on impact. Ammunition is made and packed to withstand all conditions ordinarily encountered in the field. M252 81mm Medium Extended Range Mortar - Federation of American Scientists Barrel (with blast attenuator device) The M1 became the standard American . It can provide all-weather, ground-based, close supporting, accurate, immediately 0.30, BROWNING, M1919A4, M1919A5 AND M1919A6 {TO 39A-5 AF-32} (S&I BY PROP SEE DETAILS, FOOTNOTES), GUN, MACHINE, CAL. (5) Four inches of elevation shaft are exposed, and the shaft is not bent. The safety/packing clip should be removed when the cartridge is unpacked. They are assembled with either an M524-series, M526-series, or M567 fuze. f. The open end of the socket must continue to point in the direction of fire. Target terrain, such as ice and dry sand, gives lowest burst heights, whereas water and wet ground give highest burst heights. It arms within a maximum of 2.50 seconds. He places his thumbs alongside the forefingers, being careful to keep both hands away from the muzzle. The fuze is not intended to function at charge 0. 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. ), 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). (The handle of the wrench is turned counterclockwise.) When the baseplate is in position, the first ammunition bearer lowers the breech plug into the rotating socket and rotates the barrel a quarter of a turn to lock it. 0.50, M8 (REPRINTED W/BASIC INCL C1-2) (S&I BY PROP SEE DETAILS, FOOTNOTES), FIRING TABLES FOR MACHINE GUN, CALIBER .50: BROWNING, M2 (HEAVY BARREL, TURRET TYPE) ON MOUNT, MACHINE GUN, TRAILER MOUNTED: MULTIPLE CALIBER .50 MACHINE GUN, M55 FIRING CARTRIDGE, CALIBER .50: API, M8 (S&I BY PROP SEE DETAILS, FOOTNOTES), FIRING TABLES FOR MACHINE GUN, CALIBER .50: FICED, M85 TANK, COMBAT, FULL TRACKED: 105MM GUN, M60 SERIES FIRING CARTRIDGE, CALIBER .50: API, M8 CARTRIDGE, CALIBER .50: API-T M20 CARTRIDGE, CALIBER .50: BALL, M33 CARTRIDGE, CALIBER .50: TRACER, M17 (S&I BY PROP SEE DETAILS, FOOTNOTES), MACHINE GUN, CAL. 107 Army Pentagon 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 . d. When the barrel reaches the horizontal position, and not before, the assistant gunner moves the thumb of each hand over the muzzle. He must not stand directly behind the mortar. Table 4-3. a. Attached to the arm is the cross-leveling mechanism, which is attached to the clamp assembly at its upper end. c. The gunner grasps both ends of the traverse screw assembly and supports the mortar during the subsequent drill. Secure .mil websites use HTTPS To prepare for firing, the slot is aligned in the striker with SQ or delay using the M18 fuze wrench. The 81mm mortar is a portable, mobile, medium mortar at the infantry's disposal. The M532 fuze is a radio doppler fuze that has a proximity (PROX) or SQ/IMP function. Each cartridge weighs about 10 pounds and is provided with the M223 propelling charge, consisting of four horseshoe-shaped increments fitted around the tail. If it is necessary to leave the ammunition uncovered, it should be raised on dunnage at least 6 inches above the ground. The increments are individually wrapped with waterproof bags that are not removed. .30 BROWNING, M1917 AND M1917A1; GUN, MACHINE, CAL. FT 81-AI-3 Firing Tables Mortar, 81mm: M28A1 and M29 Mortar 81mm Self a. 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. He levels all bubbles. When set at SQ, the fuze functions on point impact or graze contact. ) or https:// means youve safely connected to the .gov website. End this starting train with not less than 1 meter of inert material (dry grass, leaves, or newspapers). The contents of ammunition containers are shown by markings. SMALL DEFLECTION AND ELEVATION CHANGES. 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. Other armies count on 81mm mortar families. If the mortar section is to operate quickly and effectively in accomplishing its mission, mortar squad members must be proficient in individually assigned duties. The gunner then kicks the barrel several times with his heel in an attempt to dislodge the round. It is constructed from ductile cast iron and contains about 1.5 pounds of cyclonite (RDX)/trinitrotoluene (TNT) composition explosive. It should be destroyed in accordance with standard procedures. 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. The term "indirect fire" means firing at an enemy without having a. 120mm IHE grenade DM91. PDF Tabular Firing Tables - United States Army The assistant gunner exposes 8 inches (200 millimeters) of elevation shaft, leaving the elevation handwheel unfolded. a. Cartridges assembled with the M524 (A1, A2, A3, or A4) fuze are for use by the US Marine Corps and US Navy only. 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 official website of the United States government. He places the sight case and aiming posts to the left front of the mortar position. (See FM 7-90 for a discussion of the duties of the platoon headquarters.). He positions the lower barrel clamp against the lower stop band on the barrel and secures the upper barrel clamp. (e) If the mask is not regular throughout the sector of fire, the gunner determines the minimum mask clearance as described above. a. The sight bracket is attached to the buffer carrier, which is fitted to the traversing screw assembly. a. The cartridges are returned to their original containers. More uniform firing is obtained if ammunition is kept at the same temperature. CANNON . (d) Firing is slowed if mask clearance must be checked before each firing but this can be eliminated if minimum mask clearance is determined. Those cartridges assembled with the M524 (A1, A2, A3, or A4) fuze are for use by the US Marine Corps and US Navy only. The 81mm mortar rounds use Red Phosphorus as the smoke generating agent. It uses the M219 propelling charge and weighs about 9.1 pounds. 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. The powder increments, mainly, should not be exposed to direct sunlight. c. After the gunner has announced, "Up," the squad leader should check the mortar to determine if the exercise was performed correctly. Mortar Weapon Systems - USAASC Rheinmetall Defence - mortar systems This section discusses the characteristics and nomenclature of each component (Figure 4-2). The 81-mm mortar, M252, is a smooth-bore, muzzle-loaded, high-angle-of-fire weapon. The gunner is given an administrative command to lay the mortar on a deflection of 2860 or 2740 mils. SQUAD AND SECTION ORGANIZATION AND DUTIES, Each member of the infantry mortar squad has principle duties and responsibilities. Prev - Mk6 Mortar range table for charge 0 Next - Mk6 Mortar range table for charge 2 . When the approximate alignment is completed, the gunner signals the assistant gunner to lower the bipod by pushing down on the mortar. The gunner is given a deflection change in a fire command between 20 and 60 mils inclusive. 4-11. c. The moisture-resistant seal of the container is broken when the ammunition is to be used. (2) The breech plug is screwed tightly to the barrel. Range Minimum to maximum 83 to 5,608 meters Rate of Fire . PDF Principles of Fire Support B2c0289xq Student Handout The cartridge is painted olive drab with yellow markings and weighs about 9.05 pounds. If the barrel is hot, the gunner may then apply water to the outside of the barrel until it is cool. 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. In charge was the platoon commander - normally a lieutenant. The removable increments are fitted onto or around the shaft, depending on their type. (4) Extra increments are removed if the cartridge is to be fired with less than full charge. The round has a burst height of 600 meters and provides illumination for about 60 seconds for an area of about 1,200 meters. It is set using the bladed end of the M18 fuze wrench. He opens the cross-level handwheel, traversing handwheel, and barrel clamp. Home; Swifty. The gunner places the announced deflection on the sight (without disturbing the lay of the weapon) and looks through the sightunit. a. 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. When a large number of cartridges are needed for a mission, they may be removed from the containers and prepared. The obturating ring ensures equal muzzle velocities in hot or cold barrels by keeping all the gases in the barrel until the cartridge has fired. 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 . He makes large deflection shifts by shifting the bipod assembly and keeps the bubbles level during firing. Share sensitive information only on official, secure websites. d. The first ammunition bearer stands to the right rear of the mortar. Placing the mortar in position at night does not relieve the gunner of the responsibility of checking for mask clearance and overhead interference. Both legs are fitted with a disk-shaped foot with a spike beneath to prevent the mount from slipping. (5) Do not leave unused increments unburned in combat operational areas. (b) In selecting the exact mortar position, the leader looks quickly for mask clearance and overhead interference. The fuze threads and fuze well threads are inspected for damage. d. Multioption. 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. (4) The blast attentuator device is secured correctly. Red phosphorus/white phosphorus is used for screening, producing casualties, creating incendiary effects, and signaling. M252 mortar | Military Wiki | Fandom After the 30-minute waiting period, the dud is still dangerous but can be approached and removed carefully or destroyed in place by qualified disposal personnel. 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 fuze is set manually to proximity, point detonate, or delay modes. 81mm, 82 mm & 120 mm Medium and Heavy Mortars - GICHD The section leader, acting as FDC, has one deflection instead of two or more. Additionally, they carry the 81mm M252 mortar that can only be used in a dismounted capacity. These propellants are flash-suppressed and clean burning resulting in minimum residue, flash and blast overpressure. The fuze should already be fitted to the cartridge. The sight is laid on 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. The air burst over average types of soil ranges from 1 to 6 meters, depending on the angle of approach. b. (4) The M567 fuze is an impact fuze that has a SQ/IMP or D function. The fuze arms and functions normally when fired at any angle of elevation between 0800 and 1406 mils at charges 1 through 9. The mortar is within two turns of center of traverse. Baseplate placed against baseplate stake. Cartridges assembled with the M524 (A1, A2, A3, or A4) fuze are for use by the U.S. Marine Corps and U.S. Navy only. The first ammunition bearer puts both hands on the cooling fins under the barrel and slowly lifts the barrel until it is horizontal. An internal clock mechanism provides nine seconds of safe air travel (610 to 2,340 meters along trajectory for charge 0 through 9, respectively). HE Guided Mortar is in development. Army Publishing Directorate He then checks the sight picture to ensure he is within 20 mils of a proper sight picture. M252 81mm Medium Mortar M64A1 Sightunit. 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. The American M1 81mm Mortar, like the upcoming M2 60mm Mortar, was based on a French design by Edgar William Brandt (1880-1960). The fuze body is graduated from 0 to 25 seconds in 1-second intervals; 5-second intervals are indicated by bosses. .30, BROWNING, M1919A4 AND M2 (HEAVY BARREL), .30, M2 (REPRINTED W/BASIC INCL C1) (S&I BY PROP SEE DETAILS, FOOTNOTES), GUN, MACHINE: CAL. The standard infantry support weapon is the M-252 81mm mortar, which lobs a 10 lb. It is assembled with the M772A1 MTSQ. The aluminum tail assembly has six integral fins equally spaced around the rear, which stabilize the round in flight. It is fitted with a safety wire and pin that are removed immediately before firing. b. 81 mm HE mortar projectiles generally contain anywhere between 400 g and 680 g of HE and have a maximum range of approximately 6,500 m. 82 mm HE mortar projectiles generally contain anywhere between 392 g and 680 g of HE and have maximum ranges of between 3,000 - 5,500 m. Ammunition is typed according to use (Table 4-2). Identification. The 60mm mortar section is located in the weapons platoon of the rifle company, is armed with three 60mm mortars, and is e. The squad leader picks up the aiming posts and sight. c. Upon receiving the command REFER, REALIGN AIMING POST, two actions take place at the same time in the mortar squad. Fort Belvoir, VA 22060 The safety wire must be removed before firing. MORTAR RANGE: 500M X 100M X: FIELD TRAINING AREA 40000 Sq Ft: X STORAGE BUILDING, GENERAL PURPOSE, INSTALLATION: Area to store excess equipment X: ORGANIZATIONAL STORAGE BUILDING Arms room for Mortar equipment: X . After the barrel cools, the gunner removes the sight and firing pin. If the line of sight clears the mask, it is safe to fire. Referring and realigning aiming posts ensure that all mortars are set on the same data. 120MM Mortar System. . This section discusses the. The M252 is highly accurate up to ranges of 4500m to 5700m depending on the a. Before-firing checks include the following: (1) Ammunition should be free of moisture, rust, and dirt. . Close approach to crests, trees, towers, large buildings, parked aircraft, mechanized equipment, and similar irregularities causes functioning at heights greater than average level. They function normally in light rain; however, heavy rain, sleet, or snow can cause an increase in the number of early bursts. If water is not available, the gunner must stand clear of the mortar until the barrel is cool. 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. This round must be stored in a vertical position. If required, the gunner/assistant gunner lowers the barrel so that the breech plug engages with the open end of the socket, and he uses the barrel as a lever to move the socket. MFCS Mounted. High explosive is used for both fragmentation and blast effect against personnel and light-skinned vehicles. The superior flow characteristics of these BALL POWDER . M29, 81mm Mortar - Military Factory 81mm 120mm 60mm . Official websites use .mil Swifty 3 from scratch; Swifty 3 split-repo setup; Swifty Troubleshooting; Mods. Section I. The tabulated data of the 81-mm mortar, M252, are shown in Table 4-1. The equipment is placed out the same as for the gunner's examination (Chapter 9). Training practice is used only for training.