Mortar, 81mm, M1

Overview

Mortar, 81mm, M1
Information
Type	Medium Mortar
Place of Origin	United States of America
Designed	1930s
Produced	1930s - 1940s
In Service	1935 - Unknown
Specifications
Shell / Cartridge	81mm
Elevation	+40° to +85°
Traverse	-50.6° to +50.6° One handwheel traverse roughly equals 8.4°
Carriage / Mount	Mount, Mortar: 81mm, M4 Mount, Mortar: 81mm, M4 w/o Baseplate on Carrier, 81mm Mortar, Half-Track, M21
Dimensions
Length	1.265m
Weight	59.875kg (including M4 Mount) 20.185kg

The Mortar, 81mm, M1 is an American medium mortar developed in the 1930s.

Description

The Mortar, 81mm, M1, is a smooth-bore, muzzle-loading, high angle-of-fire weapon consisting of a tube and a base cap containing a fixed firing pin. The weapon is mounted to the Mount, Mortar: 81mm, M4 in standard operation. The Mount, Mortar: 81mm, M4 consists of a baseplate, and a bipod with controls for elevation and traverse, as well as shock absorbing springs.

The Mortar, 81mm, M1 can also be mounted in a vehicle. The Carrier, 81mm Mortar, Half-Track, M21 features the Mortar, 81mm, M1 in a forward-facing position in the rear compartment. The Mount, Mortar: 81mm, M4 is used without the baseplate in this configuration, as the vehicle comes equipped with an integrated baseplate.

Carrier, 81mm Mortar, Half-Track, M21

Ammunition

Below is a list of ammunition compatible with the Mortar, 81mm, M1. Note that some of these rounds may have restrictions in place to ensure normal operation and prevent damage or accidental injuries/death.

Cartridge, 81mm: HE, M43 Unknown "light" HE round. Cartridge, 81mm: HE, M43A1 3.402kg "light" HE round, 0.585kg Composition B. Later refit with modern fuzes (M525 / M717). Cartridge, 81mm: HE, M43A1B1 3.402kg "light" HE round, 0.585kg Composition B. Later refit with modern fuzes (M525 / M717). The B1 has minor metal part differences with little to no functional difference. Cartridge, 81mm: HE, M45 Unknown "heavy" HE round. Cartridge, 81mm: HE, M45B1 Unknown "heavy" HE round. Cartridge, 81mm: HE, M56 Unknown "heavy" HE round. Cartridge, 81mm: HE, M56A1 Unknown "heavy" HE round. Cartridge, 81mm: HE, M362 4.273kg HE round, 0.953kg Composition B. Forged steel body. Cartridge, 81mm: HE, M362A1 4.273kg HE round, 0.953kg Composition B. The A1 model does not have a forged steel body. Cartridge, 81mm: HE, M374 4.237kg HE round, 0.953kg Composition B. Cartridge, 81mm: HE, M374A2 4.237kg HE round, 0.953kg Composition B. The A2 model includes moisture-proof ignition system, and other related improvements. Cartridge, 81mm: HE, M374A2E1 4.105kg HE round, 0.953kg Composition B. Later standardized as M374A3. Cartridge, 81mm: HE, M374A3 4.105kg HE round, 0.953kg Composition B. Cartridge, 81mm: Illuminating, M301 Unknown illumination round. Cartridge, 81mm: Illuminating, M301A1 4.854kg illumination round. Fires a fin-stabilized flare, producing 500,000 candlepower for at least 50 seconds. Cartridge, 81mm: Illuminating, M301A2 4.854kg illumination round. Fires a fin-stabilized flare, producing 500,000 candlepower for at least 50 seconds. The A2 model lacks gas check bourrelet grooves and has minor dimensional differences. Cartridge, 81mm: Illuminating, M301A3 4.581kg illumination round. Fires a fin-stabilized flare, producing 500,000 candlepower for at least 50 seconds. The A3 model has interchangeable fin assembly. Cartridge, 81mm: Mortar Training Device, 81mm Sabot (Inert), M1 3.856kg training sub-caliber sabot. Cartridge, 81mm: Smoke, FS, M57 5.162kg FS smoke. These rounds were phased out in favour of the WP rounds. Cartridge, 81mm: Smoke, FS, M57A1 5.162kg FS smoke. The A1 model uses the M4A1 fin assembly instead of the M4 fin assembly. These rounds were phased out in favour of the WP rounds. Cartridge, 81mm: Smoke, WP, M57 5.162kg round with 1.842kg of WP smoke. Cartridge, 81mm: Smoke, WP, M57A1 5.162kg round with 1.842kg of WP smoke. The A1 model uses the M4A1 fin assembly instead of the M4 fin assembly. Cartridge, 81mm: Smoke, WP, M370 4.237kg round with 0.726kg of WP smoke. Cartridge, 81mm: Smoke, WP, M375 4.237kg round with 0.726kg of WP smoke. M149 fin assembly. Cartridge, 81mm: Smoke, WP, M375A1 4.237kg round with 0.726kg of WP smoke. M149 fin assembly. Cartridge, 81mm: Smoke, WP, M375A2 4.237kg round with 0.726kg of WP smoke. M170 fin assembly. Cartridge, 81mm: Smoke, WP, M375A3 4.128kg round with 0.726kg of WP smoke. M24 fin assembly. Cartridge, 81mm: TP, M43A1 3.307kg training practice round. Cartridge, 81mm: TP, M44 Unknown training practice round. Cartridge, 81mm: Training, M68 4.894kg training round. Cartridge, 81mm: Training, M445 4.894kg training round. Cartridge, 81mm: Training, T32E1 4.894kg training round. Later standardized as M445.

United States of America Weapons Interwar & World War II Period (1919 — 1945)

Infantry Weapons
Melee Weapons	Blades	Ka-Bar • M1 Bayonet • M3 Trench Knife • M1917 Bayonet • M1942 Bayonet • Marine Raider Stiletto • Mark I Trench Knife
Sidearms	Pistol	HDM • M1903 • M1908 • M1911 (A1)
	Revolver	M1917 • New Service • Official Police • Victory
Close-Quarters	Submachine Gun	M1 (A1) • M2 • M3 (A1) • M42 • M50 • M55 • M60 • M65 • M1921 • M1923 • M1926 • M1927 (A1 • A3 • A5) • M1928 (A1)
	Shotgun	Auto-5 • M31 • M37 • M520 • M620 • M1897 • M1912
Rifles	Bolt-Action Rifle	M1903 (A1 • A2 • A3 • A4) • M1917
	Battle Rifle	M1 (E1 • E2 • E3 • E4 • E5 • E6 • E8 • E9 • E10 • E11 • E12 • E13 • E14) • M1941 • T1 (E1 • E2) • T20 (E1 • E2 • E2, HB) • T22 (E1 • E2 • E2, HB) • T23 • T26 • T27 • T31 • T35 • T36 • T37
	Assault Rifle	M1 (A1 • A2 • A3) • M2 • M3
Machine Guns	Light Machine Gun	Browning M1918A2 • M1941
	Medium Machine Gun	M1917 • M1919 (A1 • A2 • A3 • A4 • A6)
	Heavy Machine Gun	M2
Anti-Materiel	Anti-Tank Rifle	[[]]
	Recoilless Rifles	M18 • M20
	Rocket Launchers	M1 (A1) • M9 (A1) • M18 • M20
	Flamethrowers	E1 • E1R1 • M1 (A1) • M2 (A1)
Grenades	Grenade Launchers	[[]]
	Rifle Grenade Launchers	M1 • M7 • M17
	Anti-Personnel Grenades	Mk 2 • MK3 • MK3A1 • MK3A2 • M1 Frangible Grenade • T13
	Anti-Tank Grenades	[[]]
	Smoke Grenades	[[]]
Mines	Anti-Personnel Mines	M3 • M16
	Anti-Tank Mines	M1 • M1A1 • M4 • M7 • M7A1 • M7A2
Other	Flare Guns	[[]]
	Other Man-Portable Explosives	M1A1 Bangalore Torpedo

Infantry Equipment
Camouflage	Camouflage	[[]]
Clothing	Backpacks	[[]]
	Body Armour	[[]]
	Bomb Suit	[[]]
	Elbow and knee pads	[[]]
	Signals & IFF	[[]]
	Suits	[[]]
	Vests & Webbing	[[]]
Headwear	Communication	[[]]
	Gas Masks & Rebreathers	[[]]
	Goggles	[[]]
	Helmets	[[]]
	Vehicle Headwear	[[]]
Optics, Detection and Surveillance	Man-Portable Radar	[[]]
	Mine Detectors	[[]]
	Night Vision Goggles	[[]]
	Periscopes	[[]]
	Rangefinders	[[]]
	Surveillance	[[]]

Artillery
Anti-Aircraft Guns	M45 Quadmount • 37mm M1 • 37mm M1A1 • 37mm M1A2 • 40mm M1 • 3-Inch M1917 • 3-Inch M1918 • 3-Inch M1 • 3-Inch M2 • 3-Inch M3 • 3-Inch M4 • 90mm M1 • 90mm M1A1 • 90mm M2 • 120mm M1
Anti-Tank Guns	37mm M3 (A1 • 57mm M1 • 75mm M1897 • 3-Inch M5 • 90mm M2 37mm T3 • 37mm T7 • 37mm T8 • 90mm T8 • 105mm T8
Coastal Artillery	3-Inch M1902 • 3-Inch M1903 • 90mm M1 • 6-Inch M1897 • 6-Inch M1900 • 6-Inch M1903 • 6-Inch M1905 • 6-Inch M1908 • 6-Inch M1 • 6-Inch T2 • 12-Inch M1890 • 12-Inch M1895 • 12-Inch M1888 • 12-Inch M1900 • 14-Inch M1907 • 14-Inch M1909 • 14-Inch M1910 • 16-Inch M1895 • 16-Inch M1919 • 16-Inch M1920 • 16-Inch Mark 2 • 16-Inch Mark 3
Field Guns	75mm M1897 • 4.5-Inch M1 • 4.5-Inch T3 • 6-Inch M1897 • 6-Inch M1900 • 6-Inch M1903 • 6-Inch M1905 • 6-Inch M1908 • 6-Inch M1 • 6-Inch T2 • 155mm M1 • 155mm M1A1 • 155mm M1A1E1 • 155mm M1A1E3 • 155mm M2 • 155mm T4 • 8-Inch M1
Howitzers	105mm M1 • 105mm M2 • 105mm T2 • 105mm M2A1 • 105mm M3 • 155mm M1918 • 155mm M1 • 8-Inch M1 • 8-Inch M2 • 240mm M1
Infantry & Mountain Guns	75mm M1 • 75mm M1A1
Mortars	60mm M2 • 81mm M1 • 4.2-Inch M2 • 12-Inch M1890 • 36-Inch Project 4712
Railroad Artillery	8-Inch VI • 8-Inch M1888 • 10-Inch M1895 • 10-Inch M1888 • 10-Inch M1900 • 14-Inch M1920
Recoilless Guns	[[]]
Rocket Artillery	[[]]
Siege Artillery	[[]]

Land Vehicle Weapons
Vehicle Machine Guns	M1919 (A4 • A4E1 • A5) • M2 (Fixed • Flexible • TT)
Standard Tank Guns	37mm M5 (E1) • 37mm M6 • 37mm M1924 (A1) • 75mm M2 • 75mm M3 • 75mm M6 • 3-inch M5 • 3-inch M6 • 3-inch M7 • 76mm M1 (A1 • A1C • A2) • 76mm T1 • 90mm M3 (A1) 37mm T21
Other Cannons Mounted on Tanks	75mm Howitzer M1 (A1) • 75mm AT Gun M1897 • 105mm Howitzer M2 • 105mm Howitzer M4 • 105mm T8 • 155mm Howitzer M1918 • 155mm Howitzer M2
Rocket Artillery	M17 • T34 (E1 • E2) • T40
Vehicle Flamethrowers	E7-7 • E9 • E14-7R2 • Navy Mk.I • Ronson
Spotlights	Canal Defence Light

Aircraft Weapons & Munitions
Aircraft Machine Guns	AN/M2 • M3
Aircraft Cannons below & including 30mm	[[]]
Aircraft Cannons above 30mm	37mm M4 • 37mm T9 • 37mm M10 • 75mm M5 • 75mm T13E1
Aircraft Rockets & Missiles	T64 H.V.A.R.
Aircraft Bombs, High Explosive	[[]]
Aircraft Bombs, Anti-Personnel	[[]]

Naval Weapons & Munitions
Naval Machine Guns	M2
Naval Cannons below & including 30mm	[[]]
Naval Cannons above 30mm	37mm M9

Sources
Books	Online	Documents
		• TM 9-2005 — Ordnance Materiel - General; Volume 3, 1942-12 • TM 9-2200 — Small Arms, Light Field Mortars, and 20-mm Aircraft Guns, 1943-10-11 • TM 9-3071-1 — 60-mm Mortars M2 and M19; 60-mm Mortar Mount M5; 60-mm Mortar Baseplate M1; 81-mm Mortars M1 and M29; and 81-mm Mortar and Mounts M4, M23A1, M23A2, and M23A3, 1967-01-12 • TM 43-0001-28 — Army Ammunition Data Sheets - Artillery, Ammunition, Guns, Howitzers, Mortars, Recoilless Rifles, Grenade Launchers, and Artillery Fuizes, 1994-10-27