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 . It is constructed from ductile cast iron and contains about 1.5 pounds of cyclonite (RDX)/trinitrotoluene (TNT) composition explosive. Cartridges assembled with the M532 fuze must be fired above charge 0. A plain leg is fitted to a stud on the elevating leg and is secured by a leg-locking handwheel. 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. He performs other duties as the squad leader directs. I say 120s are bad because they suffer from terrible dispersion even when not shooting at 6km. News. (4) The M567 fuze is an impact fuze that has a SQ/IMP or D function. At the same time, the first ammunition bearer moves out on the double to realign the aiming posts. (1) The barrel is clean and free from grease and oil both inside and out. b. If not, he may still fire at the desired range by selecting a charge zone having a higher elevation. 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 muzzle end has a short tapered lead-in which acts as a . The pile is covered with a double thickness of tarpaulin. It should be destroyed in accordance with standard procedures. The assistant gunner cleans the bore and swabs it dry. 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 places firing data on the sight and lays the mortar for deflection and elevation. (5) Four inches of elevation shaft are exposed, and the shaft is not bent. 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. REFER DEFLECTION TWO EIGHT SEVEN FIVE (2875), REALIGN AIMING POSTS. d. The gunner recovers the baseplate to the area designated by the squad leader. The first ammunition bearer puts both hands on the cooling fins under the barrel and slowly lifts the barrel until it is horizontal. (2) The barrel is locked to the baseplate, and the open end of the socket points in the direction of fire. If the situation allows for a longer waiting period, the dud can be considered safe for handling after 40 hours. a. To dismount the mortar, the squad leader commands, OUT OF ACTION. b. ) or https:// means youve safely connected to the .gov website. (3) The securing strap is correctly located, securing the barrel clamps and buffers to the plain leg. The 81mm weapons platoon consisted of the headquarters platoon and four mortar squads. When the gunner is satisfied with his sight picture he announces, "Up.". He places his thumbs alongside the forefingers, being careful to keep both hands away from the muzzle. A safety latch located at the side of the recess is used to secure the ball. 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. .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. Each squad member should be able to perform all the following premount checks: a. 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 M29 would become the standard American mortar in the upcoming Vietnam War. 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. FT 81-AI-3 Firing Tables Mortar, 81mm: M28A1 and M29 Mortar 81mm Self propelled M125A1 and M125 Carrier, 81mm Mortar Tracked XM755 Ammunition is typed according to use (Table 4-2). 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 . At the muzzle end is a cone-shaped blast attenuator device (BAD) that is fitted to reduce noise. b. M3A1 Baseplate Baseplate placed against baseplate stake. The vertical cross line of the sight is on the left edge of the aiming point. Overhead interference can be branches of trees or roofs of buildings. The terms cannon and barrel are used interchangeably in this chapter. The fuze is nicely marked and is dated 1940. e. The assistant gunner passes the round to the first ammunition bearer who inspects it for the cause of the misfire. a. b. 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. They are assembled with either an M524-series, M526-series, or M567 fuze. While the assistant gunner supports the barrel, the gunner slackens the leg-locking handwheel, releases the locating catch, and positions the plain leg. The cartridges are painted olive drab with yellow markings. The squad leader indicates the direction of fire when mounting. One-quarter turn on the adjusting nut equals one turn of the traversing handwheel. When firing under the control of an FDC, he reports to the FDC that mask clearance cannot be obtained at a certain elevation. 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. This is the inert PD fuze type "IR-81" used by the Italians for their 81mm mortar rounds during WWII. Fort Belvoir, VA 22060 An M18 fuze wrench is used to change settings. Referring and realigning aiming posts ensure that all mortars are set on the same data. To set for delay, the selector slot should be rotated clockwise until it is aligned with the "D" mark on the ogive. 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 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. 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. If the barrel is hot, the gunner may then apply water to the outside of the barrel until it is cool. Its range and explosive power is greater than the M224, yet it is still light enough to be man . Types of rounds, classification, and characteristics for the 81-mm mortar, M252. c. Upon receiving the command REFER, REALIGN AIMING POST, two actions take place at the same time in the mortar squad. The cartridge is painted olive drab with yellow markings and weighs about 9.05 pounds. Examples are: The fuze has a safety wire that must be removed before firing. e. The second ammunition bearer stands to the right rear of the mortar behind the ammunition bearer. DESCRIPTION. Red phosphorus/white phosphorus--M819 and M375-series. Designed by Thingsym. Other armies count on 81mm mortar families. It provides illumination for about 60 seconds with 600,000 candlepower illumination. It engages the 1 3/4-inch flats on the setting ring or the fuze head. This section discusses the. c. The assistant gunner stands to the right of the mortar, facing the barrel and ready to load. The superior flow characteristics of these BALL POWDER . (c) The gunner determines mask and overhead clearance by sighting along the barrel with his eye near the breech plug. f. If the above procedure fails to remove the misfire, the barrel must be kept horizontal. 0.30, BROWNING, M1917A1; GUN, MACHINE: CAL. The assistant gunner exposes 8 inches (200 millimeters) of elevation shaft, leaving the elevation handwheel unfolded. The gunner then kicks the barrel several times with his heel in an attempt to dislodge the round. (5) Do not leave unused increments unburned in combat operational areas. That is generally how I use mortars. e. The gunner centers the elevation bubble. More uniform firing is obtained if ammunition is kept at the same temperature. The ignition cartridge (with primer) is fitted into the base of the fin shaft. The 81-mm mortar, M252, is a smooth-bore, muzzle-loaded, high-angle-of-fire weapon. MFCS Dismounted. .50 MACHINE GUN, M3; FIRING CARTRIDGE, CAL. Official websites use .mil 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. News. He uses the chain of command to assist him in effecting his command and supervising duties. 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. Bear in mind that these are my personal opinions, experiences, and . 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. Range Minimum to maximum 83 to 5,608 meters Rate of Fire . [1] [2] Many countries use or used an 81 mm mortar in their armed forces. b. The enemy will use them. If he is not within 20 mils, the gunner and assistant gunner must make another large shift before moving on. The striker has been modified to be able to use German and Italian patterns of 81mm mortar . 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. 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. b. The floating firing pin located within the primer has approximately 1/16 of an inch to move around. The gunner places the announced deflection on the sight (without disturbing the lay of the weapon) and looks through the sightunit. This ensures a maximum traversing and elevating capability after making the movement. 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. Cartridges assembled with the M532 fuze must be fired above charge 0. The propellant increments are ignited, which produce rapidly expanding gases that force the cartridge from the barrel. High explosive--M821, M889, M374-series, and M362. 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. Excess increments should not accumulate near the mortar positions but are removed to a designated place of burning and destroyed. The propelling charge consists of an ignition cartridge and removable propellant increments. He indicates the initial direction of fire by pointing in that direction and commands ACTION. M120/M121 120 mm Mortar. The mortar also offered the promised increase in range as well, allowing fire teams to engage the enemy at distance. The cartridge must not be fired below charge 3. The safety wire must be removed before firing. After the mortar is mounted, the gunner makes a thorough check. With the clamps facing away from him, the assistant gunner traverses the buffer carrier to the traversing handwheel and folds the handle. It is set using the bladed end of the M18 fuze wrench. A .mil website belongs to an official government organization in the United States. He has the duty of preparing the ammunition and passing it to the assistant gunner. Safety before firing is provided by a safety wire, which must be removed just before firing. Table 4-1. on Amazon.com. Proximity (VT). The 81-mm mortar, M252, is a smooth-bore, muzzle-loaded, high-angle-of-fire weapon. The components of the mortar consist of a canon, sight, mount, and baseplate. Several types of HE ammunition are used in the 81-mm mortar, M252. If the fuze does not function as set, it automatically functions at the next lower setting. The 81mm mortar is a portable, mobile, medium mortar at the infantry's disposal. These fuzes use a clockwork mechanism to delay functioning for a specific time. If you look at the table above, you'll see that at 1.5km range, 120mm mortars have nearly 33% more dispersion than 80mm mortars.Try testing 80mm mortars and 120mm mortars at 1.5km against . The M301A3 cartridge has a cylindrical body that contains an illuminating candle and parachute assembly. The gunner can depress the barrel, if necessary, to provide easier access to the firing pin. He places the sight case and aiming posts to the left front of the mortar position. (2) Color code. Secure .mil websites use HTTPS f. Ammunition should be stored under cover. Powered by Hugo. This is accomplished by depressing the barrel until the top of the mask is clear. 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. The fuze wrench, M18, assembles the fuze to the cartridge, and the bladed tip on the end sets PD-type fuzes. He positions the lower barrel clamp against the lower stop band on the barrel and secures the upper barrel clamp. See Chapter 3, paragraph 3-14 for a detailed discussion of malfunctions. a. Cartridges are shipped with a complete propelling charge, an ignition cartridge, and primer. These cartridges are used first in subsequent firing so that once-opened stocks can be kept to a minimum. 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). The fuze setter, M25, sets M84-series time fuzes. This document (FT 81 B3, abridged) consists of two pages, each with a separate table. It can provide all-weather, ground-based, close supporting, accurate, immediately When set at delay, the fuze train causes a 0.05-second delay before functioning. The baseplate (Figure 4-5) is of one-piece construction, and supports and aligns the mortar for firing. (8) To help minimize the occurrence of short rounds and or duds, unpackaged ammunition that has been dropped should not be fired. High angles of approach (near vertical) give the lowest burst heights. The M375 cartridge uses the M90 propelling charge while the M375A2 and M375A1 cartridges use the M90A1 propelling charge. The lower clamp is shaped and bored on each side to house the buffer cylinders. (3) From this train, extend a starting train that will burn against the wind of single increments laid end to end. 107 Army Pentagon g. The barrel clamps can be moved along the barrel to counter large changes in elevation.