9301 Chapek Road., Bldg.1458 REFERRING OF THE SIGHT AND REALIGNMENT OF AIMING POSTS USING M64 SIGHT. A .mil website belongs to an official government organization in the United States. (4) The blast attentuator device is secured correctly. The propelling charges are assembled around the fin assembly shaft. Their firing positions and principal duties are as follows: a. The M853 cartridge (M252 only) has a cylindrical body that contains an illuminating candle and parachute assembly. Figure 4-7. To make the shift, the gunner places the fingers of his right hand in the muzzle and his left hand on the left leg. If, upon removal of the safety wire, a buzzing sound in the fuze is heard, the round should not be used. 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). on Amazon.com. Notches in the setter engage ribs in the setting ring of the fuze. 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. It contains white phosphorus that produces white smoke on contact with air. The M252 is highly accurate up to ranges of 4500m to 5700m depending on the 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. e. The pull wire and safety wire are removed from the fuze just before firing. 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. Prev - Mk6 Mortar range table for charge 0 Next - Mk6 Mortar range table for charge 2 . In addition to supervising the emplacement, laying, and firing of the mortar, he supervises all other squad activities. He knocks down the near aiming post and proceeds to the far aiming post. After the rounds have been removed, they should always be handled with two hands to prevent accidental dropping. a. 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. a. (5) Four inches of elevation shaft are exposed, and the shaft is not bent. 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) . (7) When opening an ammunition box, the ammunition bearer ensures the box is horizontal to the ground, not nose- or fin-end up. PDF Tabular Firing Tables - United States Army The fuze is screwed into the cartridge body, and it is seated and secured using an M18 wrench. The barrel clamp, which consists of an upper and lower clamp, is situated at the top. (2) The M84 fuze is a single-purpose, powder-train, mechanical-time fuze used with the 81-mm M301A1 and M301A2 illuminating cartridges. When cartridges have been prepared for firing, but are not used, all powder increments and safety wires are replaced. Standard A ammunition for the M29A1 mortar is Standard B for the M252 mortar (, Light green Yellow band with red markings. 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. The fuze is not intended to function at charge 0. This may cause the firing pin to ignite the charges if the cartridge is dropped on the fin end (. b. The mortar is within two turns of center of traverse. The table on the right describes the three most common setups. PDF 81-mm MORTAR, M252 - GlobalSecurity.org The propellant train (except the training cartridge) consists of an ignition cartridge and propellant charges. It engages the 1 3/4-inch flats on the setting ring or the fuze head. Section I. He moves the mortar until the vertical line of the sight is aligned approximately on the aiming post. He maintains the ammunition for firing and provides local security for the mortar position. These propellants are flash-suppressed and clean burning resulting in minimum residue, flash and blast overpressure. d. The ammunition is protected from mud, sand, dirt, and water. It has a time setting of up to 25 seconds. Burst Height. M120/M121 120 mm Mortar. The propellant increments are ignited, which produce rapidly expanding gases that force the cartridge from the barrel. (4) The bipod locking latch is locked, securing the barrel clamps. High explosive--M821, M889, M374-series, and M362. 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. (4) Extra increments are removed if the cartridge is to be fired with less than full charge. It has four function settings: PRX (proximity) causes the cartridge to explode between 3 and 13 feet above the ground; NSB (near-surface burst) causes the cartridge to explode up to 3 feet above the ground; IM (impact) causes the cartridge to explode on contact; and DLY (delay) incorporates a 0.05-second delay in the fuze train before exploding the cartridge. At the same time, the first ammunition bearer moves out on the double to realign the aiming posts. They are fuzed with the M524-series, M256-series, or M532. It is light enough to be portable when broken down into. The cartridge is dropped down the barrel, fin-end first. He ensures that the firing pin recess is facing upwards. (4) The M567 fuze is an impact fuze that has a SQ/IMP or D function. When the approximate alignment is completed, the gunner signals the assistant gunner to lower the bipod by pushing down on the mortar. 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. b. Mortars are indirect-fire weapon systems. Each round is stenciled with the ammunition lot number, type of round, type of filler, and caliber. M327 mortar is an extended range mortar system operated by Marine Corps Artillery Units. As soon as the sight data are announced, the gunner places it on the sight. The fuze arms and functions normally when fired at any angle of elevation between 0800 and 1406 mils at charges 1 through 9. e. Care, Handling, and Preservation. The Marines' Trusty Mortar Is Getting a Major Upgrade - Popular Mechanics MC Medical Guide; Client-side mods; TFAR 1.x for players; HE ammunition is used against personnel and materiel. 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). Long Range PGK. It comes preset to function on SQ/IMP, and the selector slot should align with the SQ mark on the ogive. (1) The barrel is clean and free from grease and oil both inside and out. Training practice is used only for training. The squad leader stands behind the mortar where he can command and control his squad. The cartridges are returned to their original containers. The M853 and M301A3 illuminating ammunition are described herein. 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. The 81mm mortar rounds use Red Phosphorus as the smoke generating agent. Cartridges assembled with the M532 fuze must be fired above charge 0. The cartridges are painted olive drab with yellow markings. The wrench (P/N 9349539) sets M772 MT and M768 time fuzes. The first ammunition bearer puts both hands on the cooling fins under the barrel and slowly lifts the barrel until it is horizontal. These cartridges are used first in subsequent firing so that once-opened stocks can be kept to a minimum. The assistant gunner checks the bipod and ensures that--. b. The leg-locking handwheel must then be tightened by hand, ensuring the teeth on either side are correctly meshed. [1] [2] Many countries use or used an 81 mm mortar in their armed forces. d. Multioption. It has no safety pins or wires to reduce preparation time. (2) Burn all dead grass or brush within 30 meters around the burning place. Red phosphorus cartridges (M252 only) are stored the same as HE cartridges. All mortar cartridges are painted to prevent rust and to identify their type. If not, the cartridge is placed on its side, and the closing plug is removed using an M18 fuze wrench. The 81mm mortar is a portable, mobile, medium mortar at the infantry's disposal. Tabular Firing Tables TFT ORDER FORM 1.Select "Mortar" 2.Select which mortar caliber 3.Select mortar system nomenclature 4.Select which TFTs to order 5.Put in quantity and click "Add TFTs" 6.Click "Next" TFT JUSTIFICATION 1.Put in TFT Ordering Justification 2.Click "Next" SHIPPING INFORMATION 1.Fill out all required fields The platoon leader commands the platoon and supervises the training of the elements. TM - Technical Manuals (Range 9) TM - Technical Manuals (Range 10) TM - Technical Manuals (Range 11-4) TM - Technical Manuals (Range 11-5) . DESCRIPTION. (2) The ribs and braces have no breaks, cracks, or dents. That is generally how I use mortars. Mortar, 81mm M1 - Military Factory 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. The M375A3 cartridge is ballistically similar to the M374A3 (HE) cartridge. 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 term "indirect fire" means firing at an enemy without having a. a. It is especially useful if the baseplate sinks deep into the ground during prolonged firing. He then checks the sight picture to ensure he is within 20 mils of a proper sight picture. (1) The M772A1 fuze is a MTSQ. 4-4. Figure 4-8. M252 81mm Medium Extended Range Mortar - Specifications XM1210. MFCS Mounted. The 81-mm mortar, M252, is a smooth-bore, muzzle-loaded, high-angle-of-fire weapon. (1) The M935 fuze has two function settings: impact and delay. Powered by Hugo. He may assist the gunner in shifting the mortar when the gunner is making large deflection changes. Mortar Weapon Systems - USAASC Types of rounds, classification, and characteristics for the 81-mm mortar, M29A1 (Standard B for the 81-mm mortar, M252). 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. Red phosphorus rounds can be fired from the M29/M29A1 at a reduced charge (maximum charge = charge 2). See Chapter 3, paragraph 3-14 for a detailed discussion of malfunctions. The mortar also offered the promised increase in range as well, allowing fire teams to engage the enemy at distance. The terms cannon and barrel are used interchangeably in this chapter. The powder increments, mainly, should not be exposed to direct sunlight. The air burst over average types of soil ranges from 1 to 6 meters, depending on the angle of approach. 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. It arms within a maximum of 2.50 seconds. M252 81mm Medium Mortar high-explosive bomb at a range of about three miles. 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), [email protected], GUN, MACHINE, CAL. It can be set from 3 to 55 seconds at half-second intervals. . The M301A3 cartridge has a cylindrical body that contains an illuminating candle and parachute assembly. .30, BROWNING, M1919A4 AND M2 (HEAVY BARREL), .30, M2 (REPRINTED W/BASIC INCL C1) (S&I BY PROP SEE DETAILS, FOOTNOTES), GUN, MACHINE: CAL. FM 23-90 Chptr 4 81-mm Mortar, M252 - GlobalSecurity.org e. The squad leader picks up the aiming posts and sight. The gunner is given a deflection change in a fire command between 20 and 60 mils inclusive. c. The first ammunition bearer ensures that each cartridge is clean, the safety pin is present, and the ignition cartridge is in good condition. 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. 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. It uses the M205 propelling charge, consisting of four horseshoe-shaped increments fitted around the tail. b. The fuze threads and fuze well threads are inspected for damage. This document (FT 81 B3, abridged) consists of two pages, each with a separate table. An internal clock mechanism provides nine seconds of safe air travel (610 to 2,340 meters along trajectory for charge 0 through 9, respectively). The leg-locking handwheel must then be tightened, ensuring the teeth are correctly meshed. The second page includes a chart with range and deflection (presumably for the same kind of shells), as well as notes which give additional instructions. Correctly applying and performing these duties enables the mortar section to perform as an effective fighting team. 81mm, 82 mm & 120 mm Medium and Heavy Mortars - GICHD To dismount the mortar, the squad leader commands, OUT OF ACTION. If the round fires, the mortar is re-laid on the aiming point and firing is continued. The American M1 81mm Mortar, like the upcoming M2 60mm Mortar, was based on a French design by Edgar William Brandt (1880-1960).